首页 > 最新文献

物理学报最新文献

英文 中文
Dissipation-Induced Recurrence of Non-Hermitian Edge Burst 非厄米边爆发的耗散诱导递推
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230338
Ren Cui-Cui, Yin Xiang-Guo
In quantum mechanics, the Hermitian Hamiltonian is generally used to describe the ideal closed quantum system, but in reality, the physical system is closely related to the environment, and the open quantum system coupled to the environment can be described by the equivalent non-Hermitian Hamiltonian to a certain extent. Among them, the dissipation intensity is closely related to the dynamic properties of non-Hermitian quantum systems. Therefore, it is of great practical significance to study how dissipation affects particle loss. In this paper, the dynamic law related to dissipation intensity in one-dimensional non-Hermitian systems under open boundary conditions is studied, and it is found that dissipation can induce the recurrence of edge burst. After the time-dependent evolution of the particles in the one-dimensional non-Hermitian dissipative lattice system with open boundary conditions, there is an edge burst in the system, that is, there is a large probability of particle loss at the edge, and the edge burst disappears after increasing the intensity of intracellular transition. It is found that if the dissipation intensity is increased or decreased, the edge burst will reappear. This kind of reappearance is different from the original edge burst, which is mainly manifested in the loss probability distribution of particles from the edge distribution to the volume distribution, which is due to the different probability of particle motion direction in the two cases. Under the re-induced edge burst, the particles move from the initial position to the left and right directions, and the left side rebounds after reaching the boundary, forming a more obvious loss probability at the edge and gradually decreasing to the body area. In the original edge burst, the probability of particles only moving to the left is larger, and the 'trapped' is completely dissipated at the edge, forming a distribution with an independent loss peak at the edge, the movement to the left is due to due to the non-Hermitian skin effect. The deeper reason for different movement directions is related to the defect of non-Hermitian system far from parity-time symmetry breaking. Under the parameter near the parity-time symmetry breaking defect, the loss probability of the particle is unilateral distribution, and the loss probability of the particle moving to both sides is bilateral distribution when it is far away. This is the description of the dissipation-induced edge burst recurrence phenomenon and its characteristics. In addition, this paper also studies the influence of impurity barrier on the probability distribution of particle loss in non-Hermitian dynamics. The results show that placing a small barrier on the non-dissipative A-site can obviously hinder the particle motion, and when the barrier increases to a certain height, its influence on the particle motion tends to be unchanged. And the barrier at the dissipative B lattice has little effect on the dynamics.
在量子力学中,厄米哈密顿量一般用来描述理想的封闭量子系统,但在现实中,物理系统与环境密切相关,与环境耦合的开放量子系统在一定程度上可以用等效的非厄米哈密顿量来描述。其中,耗散强度与非厄米量子系统的动力学性质密切相关。因此,研究耗散对颗粒损耗的影响具有重要的现实意义。本文研究了开放边界条件下一维非厄米系统耗散强度的动力学规律,发现耗散可以引起边缘突发的重复发生。在开放边界条件下的一维非厄米耗散晶格系统中,粒子经过随时间的演化后,系统中存在边缘爆裂现象,即粒子在边缘处有较大的损失概率,增加胞内跃迁强度后,边缘爆裂现象消失。研究发现,增大或减小耗散强度,都会重新出现边缘爆裂。这种再现与原始边缘爆发不同,主要表现在粒子从边缘分布到体积分布的损失概率分布上,这是由于两种情况下粒子运动方向的概率不同造成的。在再次诱导的边缘爆裂下,粒子从初始位置向左右方向移动,左侧到达边界后反弹,在边缘处形成更明显的损失概率,并逐渐减小到体面积。在原始边缘爆发中,粒子只向左移动的概率更大,“被困”的粒子在边缘完全耗散,在边缘形成一个具有独立损耗峰的分布,向左移动是由于非厄米集肤效应。运动方向不同的深层原因与非厄米系统远离奇偶时间对称性破缺的缺陷有关。参数在奇偶时间对称性破缺缺陷附近时,粒子的损失概率为单侧分布,粒子向两侧移动时的损失概率为双侧分布。这是对耗散引起的边缘爆发重现现象及其特征的描述。此外,本文还研究了杂质势垒对非厄米动力学中粒子损失概率分布的影响。结果表明,在非耗散a位上放置一个小的势垒可以明显阻碍粒子的运动,当势垒增加到一定高度时,对粒子运动的影响趋于不变。耗散B晶格的势垒对动力学的影响很小。
{"title":"Dissipation-Induced Recurrence of Non-Hermitian Edge Burst","authors":"Ren Cui-Cui, Yin Xiang-Guo","doi":"10.7498/aps.72.20230338","DOIUrl":"https://doi.org/10.7498/aps.72.20230338","url":null,"abstract":"In quantum mechanics, the Hermitian Hamiltonian is generally used to describe the ideal closed quantum system, but in reality, the physical system is closely related to the environment, and the open quantum system coupled to the environment can be described by the equivalent non-Hermitian Hamiltonian to a certain extent. Among them, the dissipation intensity is closely related to the dynamic properties of non-Hermitian quantum systems. Therefore, it is of great practical significance to study how dissipation affects particle loss. In this paper, the dynamic law related to dissipation intensity in one-dimensional non-Hermitian systems under open boundary conditions is studied, and it is found that dissipation can induce the recurrence of edge burst. After the time-dependent evolution of the particles in the one-dimensional non-Hermitian dissipative lattice system with open boundary conditions, there is an edge burst in the system, that is, there is a large probability of particle loss at the edge, and the edge burst disappears after increasing the intensity of intracellular transition. It is found that if the dissipation intensity is increased or decreased, the edge burst will reappear. This kind of reappearance is different from the original edge burst, which is mainly manifested in the loss probability distribution of particles from the edge distribution to the volume distribution, which is due to the different probability of particle motion direction in the two cases. Under the re-induced edge burst, the particles move from the initial position to the left and right directions, and the left side rebounds after reaching the boundary, forming a more obvious loss probability at the edge and gradually decreasing to the body area. In the original edge burst, the probability of particles only moving to the left is larger, and the 'trapped' is completely dissipated at the edge, forming a distribution with an independent loss peak at the edge, the movement to the left is due to due to the non-Hermitian skin effect. The deeper reason for different movement directions is related to the defect of non-Hermitian system far from parity-time symmetry breaking. Under the parameter near the parity-time symmetry breaking defect, the loss probability of the particle is unilateral distribution, and the loss probability of the particle moving to both sides is bilateral distribution when it is far away. This is the description of the dissipation-induced edge burst recurrence phenomenon and its characteristics. In addition, this paper also studies the influence of impurity barrier on the probability distribution of particle loss in non-Hermitian dynamics. The results show that placing a small barrier on the non-dissipative A-site can obviously hinder the particle motion, and when the barrier increases to a certain height, its influence on the particle motion tends to be unchanged. And the barrier at the dissipative B lattice has little effect on the dynamics.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"16 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90132965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Soliton Solutions of the Spin-Orbit Coupled Binary Bose-Einstein Condensate System 自旋-轨道耦合二元玻色-爱因斯坦凝聚系统的孤子解
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20222319
Li Xin-Yue, Qi Juan-Juan, Zhao Dun, Liu Wu-ming
In a quantum system with spin, spin-orbit coupling is manifested by linking the spin angular momentum of a particle with its orbital angular momentum, which leads to many exotic phenomena. The experimental realization of synthetic spin-orbit coupling effects in ultra-cold atomic systems provides a completely new platform for exploring quantum simulations. In a spinor Bose-Einstein condensate, the spin-orbit coupling can change the properties of the system significantly, which offers a great opportunity to investigate the influence of spin-orbit coupling to the quantum state at the macroscopic level. As typical states of macroscopic quantum effects, solitons in spin-orbit coupled Bose-Einstein condensates can be manipulated by spin-orbit coupling directly, this makes the study on spin-orbit coupled Bose-Einstein condensates become one of the hottest topics in the research of ultracold atomic physics in recent years. This paper investigates exact vector soliton solutions of the Gross-Pitaevskii equation for the one-dimensional spin-orbit coupled binary Bose-Einstein condensates, which has four parameters μ,δ,α and β, where μ denotes the strength of the spin-orbit coupling, δ is the detuning parameter,α and β are the parameters of the self-and cross-interaction, respectively. For the case β=α, by a direct ansatz, two kinds of stripe solitons, namely, the oscillating dark-dark solitons are obtained; meanwhile, a transformation is presented such that from the solutions of the integrable Manakov system, one can get soliton solutions for the spin-orbit coupled Gross-Pitaevskii equation. For the case β=3α, a bright-W type soliton for α>0 and a kink-antikink type soliton for α<0 are presented. It is found that the relation between μ and δ can affect the states of the solitons. Based on these solutions, the corresponding dynamics and the impact of the spin-orbit coupling effects on the quantum magnetization and spin-polarized domains are discussed. Our results show that spin-orbit coupling can result in rich kinds of soliton states in the two-component Bose gases, including the stripe solitons as well as the classical non-stripe solitons, and various kinds of multi-solitons. Furthermore, spin-orbit coupling has remarkable influence on the behaviors of quantum magnetization. In the experiments of Bose-Einstein condensates, there have been many different methods to observe the soliton states of the population distribution, the magnetic solitons, and the spin domains, so our results provide some possible options for the related experiments.
在有自旋的量子系统中,粒子的自旋角动量与其轨道角动量相联系,表现为自旋-轨道耦合,从而导致许多奇异现象。超冷原子系统合成自旋轨道耦合效应的实验实现为探索量子模拟提供了一个全新的平台。在旋量玻色-爱因斯坦凝聚体中,自旋-轨道耦合可以显著地改变系统的性质,这为在宏观水平上研究自旋-轨道耦合对量子态的影响提供了很好的机会。自旋-轨道耦合玻色-爱因斯坦凝聚体中的孤子作为宏观量子效应的典型状态,可以通过自旋-轨道耦合直接操纵,这使得自旋-轨道耦合玻色-爱因斯坦凝聚体的研究成为近年来超冷原子物理研究的热点之一。本文研究了一维自旋-轨道耦合二元玻色-爱因斯坦凝聚体的Gross-Pitaevskii方程的精确矢量孤子解,该凝聚体具有四个参数μ、δ、α和β,其中μ表示自旋-轨道耦合强度,δ表示失谐参数,α和β分别表示自旋-轨道耦合和相互作用的参数。对于β=α的情况,通过直接解析得到两种条纹孤子,即振荡的暗-暗孤子;同时,给出了由可积Manakov系统的解得到自旋-轨道耦合Gross-Pitaevskii方程的孤子解的变换。在β=3α的情况下,得到了α>0的亮w型孤子和α<0的扭结-反扭结型孤子。发现μ和δ之间的关系会影响孤子的态。在此基础上,讨论了相应的动力学以及自旋轨道耦合效应对量子磁化和自旋极化畴的影响。结果表明,自旋轨道耦合可以在双组分玻色气体中产生丰富的孤子态,包括条纹孤子、经典非条纹孤子和各种多孤子。此外,自旋-轨道耦合对量子磁化行为有显著影响。在玻色-爱因斯坦凝聚体的实验中,已经有许多不同的方法来观察种群分布、磁孤子和自旋域的孤子态,因此我们的结果为相关实验提供了一些可能的选择。
{"title":"Soliton Solutions of the Spin-Orbit Coupled Binary Bose-Einstein Condensate System","authors":"Li Xin-Yue, Qi Juan-Juan, Zhao Dun, Liu Wu-ming","doi":"10.7498/aps.72.20222319","DOIUrl":"https://doi.org/10.7498/aps.72.20222319","url":null,"abstract":"In a quantum system with spin, spin-orbit coupling is manifested by linking the spin angular momentum of a particle with its orbital angular momentum, which leads to many exotic phenomena. The experimental realization of synthetic spin-orbit coupling effects in ultra-cold atomic systems provides a completely new platform for exploring quantum simulations. In a spinor Bose-Einstein condensate, the spin-orbit coupling can change the properties of the system significantly, which offers a great opportunity to investigate the influence of spin-orbit coupling to the quantum state at the macroscopic level. As typical states of macroscopic quantum effects, solitons in spin-orbit coupled Bose-Einstein condensates can be manipulated by spin-orbit coupling directly, this makes the study on spin-orbit coupled Bose-Einstein condensates become one of the hottest topics in the research of ultracold atomic physics in recent years. This paper investigates exact vector soliton solutions of the Gross-Pitaevskii equation for the one-dimensional spin-orbit coupled binary Bose-Einstein condensates, which has four parameters μ,δ,α and β, where μ denotes the strength of the spin-orbit coupling, δ is the detuning parameter,α and β are the parameters of the self-and cross-interaction, respectively. For the case β=α, by a direct ansatz, two kinds of stripe solitons, namely, the oscillating dark-dark solitons are obtained; meanwhile, a transformation is presented such that from the solutions of the integrable Manakov system, one can get soliton solutions for the spin-orbit coupled Gross-Pitaevskii equation. For the case β=3α, a bright-W type soliton for α>0 and a kink-antikink type soliton for α<0 are presented. It is found that the relation between μ and δ can affect the states of the solitons. Based on these solutions, the corresponding dynamics and the impact of the spin-orbit coupling effects on the quantum magnetization and spin-polarized domains are discussed. Our results show that spin-orbit coupling can result in rich kinds of soliton states in the two-component Bose gases, including the stripe solitons as well as the classical non-stripe solitons, and various kinds of multi-solitons. Furthermore, spin-orbit coupling has remarkable influence on the behaviors of quantum magnetization. In the experiments of Bose-Einstein condensates, there have been many different methods to observe the soliton states of the population distribution, the magnetic solitons, and the spin domains, so our results provide some possible options for the related experiments.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"6 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90188703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Design and fabrication of the superconducting single-photon detector operating at the 5 - 10 micrometer wavelength band 5 - 10微米波段超导单光子探测器的设计与制造
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20221594
Chen Qi, Dai Yue, Li Fei-Yan, Zhang Biao, Li Hao-Chen, Tan Jing-Rou, Wang Xiao-Han, He Guang-Long, Fei Yue, Wang Hao, Zhang La-Bao, Kang Lin, Chen Jian, Wu Pei-heng
High-performance mid-wave and long-wave infrared single-photon detectors not only have significant research value in the fields of infrared astronomy and defense technology, but are also challenging to be realized in the field of single-photon detection technology. Superconducting nanowire single-photon detectors (SNSPDs) have shown excellent performance in the near-infrared band. However, how to further improve the cutoff wavelength λc is a topic of widespread concern. In this paper, the method for improving λc by applying the regulation of the superconducting disorder is discussed, and a detector with an operating wavelength band of 5 - 10 μm is designed and fabricated. Studies have shown that the multiplication and diffusion behaviors of the quasiparticles always occur during the photon detection events, although the microscopic photodetection mechanism of SNSPD still lacks a perfect theoretical explanation. Therefore, the theoretical analysis mainly considers the influence of the quasiparticles in this paper, and the mathematical formula of the detection cutoff wavelength λc can be obtained based on the phenomenological quasiparticle diffusion model. Furthermore, the disorder-dependent superconducting phase transition temperature Tc, superconducting energy gap D, and electron thermalization time τth are also considered, in order to get more precise results.Theoretical analysis suggests that the increase in the sheet resistance Rs, which evaluates the disorder strength, will help to increase λc. For example, when the nanowire width is kept at 30 nm and Rs > 380 Ω/□, it can be deduced that λc is larger than 10 μm.Experimentally, the active area of the device consists of a straight superconducting nanowire with a length of 10 μm and a width of 30 nm, so that it can effectively reduce the probability of the defects on the nanowire and avoid the current crowding effect. We have fabricated a 30 nm-wide Mo0.8Si0.2 mid infrared SNSPD, which has a cutoff wavelength λc no more than 5 μm, the effective strength of the disorder - the film sheet resistance Rs = 248.6 Ω/□. As a comparison, the sheet resistance, which is controlled by the film thickness, is increased to about 320 Ω/□ in this experiment.It is demonstrated that the Mo0.8Si0.2 detector with Rs ~320 Ω/□ can achieve saturated quantum efficiency at a wavelength of 6 μm. Furthermore, 53% quantum efficiency at the wavelength of 10.2 μm can be obtained when the detector works at a bias current of 0.9 ISW (ISW is the superconducting transition current), and it can theoretically reach a maximum value of 92% if the compression of switching current is excluded. Therefore, it can be predicted that the disorder regulation may become another efficient approach for designing high-performance mid-wave and long-wave infrared SNSPDs, in addition to the optimization of the superconducting energy gap and the cross section of superconducting nanowire.However, the continuous increase in the disorder will cause a d
高性能中波和长波红外单光子探测器不仅在红外天文和国防技术领域具有重要的研究价值,而且在单光子探测技术领域也具有挑战性。超导纳米线单光子探测器(SNSPDs)在近红外波段表现出优异的性能。然而,如何进一步提高截止波长λc是一个广泛关注的话题。本文讨论了利用超导无序调节来提高λc的方法,设计并制作了工作波段为5 ~ 10 μm的探测器。研究表明,准粒子的倍增和扩散行为总是发生在光子探测事件中,尽管SNSPD的微观光探测机制仍然缺乏完善的理论解释。因此,本文的理论分析主要考虑准粒子的影响,基于现象学准粒子扩散模型可以得到探测截止波长λc的数学公式。此外,为了得到更精确的结果,还考虑了无序相关的超导相变温度Tc、超导能隙D和电子热化时间τth。理论分析表明,评价无序强度的板电阻Rs的增加有助于λc的增加。例如,当纳米线宽度为30 nm, Rs > 380 Ω/□时,λc大于10 μm。实验中,该器件的有源区域由一条长10 μm、宽30 nm的直线型超导纳米线组成,这样可以有效降低纳米线上缺陷的概率,避免电流拥挤效应。我们制备了一个30 nm宽的Mo0.8Si0.2中红外SNSPD,其截止波长λc不大于5 μm,无序的有效强度-薄膜电阻Rs = 248.6 Ω/□。相比之下,在本实验中,由薄膜厚度控制的片材电阻增加到320 Ω/□左右。结果表明,Rs ~320 Ω/□的Mo0.8Si0.2探测器可以在6 μm波长处达到饱和量子效率。当偏置电流为0.9 ISW (ISW为超导跃迁电流)时,探测器在10.2 μm波长处的量子效率可达53%,在排除开关电流压缩的情况下,量子效率理论上可达到92%的最大值。因此,可以预见,除了优化超导能隙和超导纳米线截面外,无序调节可能成为设计高性能中波和长波红外snspd的另一有效途径。但是,从探测器的制造和应用角度来看,无序度的持续增加将导致探测器的超导相变温度Tc和ISW的降低。当纳米线宽度超窄时,这种下降趋势尤为明显,不利于探测器的信号读出。因此,探索最佳的失序调节技术,平衡工作温度、信噪比和截止波长之间的关系,对于开发高性能中波和长波红外snspd具有重要的科学和应用价值。
{"title":"Design and fabrication of the superconducting single-photon detector operating at the 5 - 10 micrometer wavelength band","authors":"Chen Qi, Dai Yue, Li Fei-Yan, Zhang Biao, Li Hao-Chen, Tan Jing-Rou, Wang Xiao-Han, He Guang-Long, Fei Yue, Wang Hao, Zhang La-Bao, Kang Lin, Chen Jian, Wu Pei-heng","doi":"10.7498/aps.72.20221594","DOIUrl":"https://doi.org/10.7498/aps.72.20221594","url":null,"abstract":"High-performance mid-wave and long-wave infrared single-photon detectors not only have significant research value in the fields of infrared astronomy and defense technology, but are also challenging to be realized in the field of single-photon detection technology. Superconducting nanowire single-photon detectors (SNSPDs) have shown excellent performance in the near-infrared band. However, how to further improve the cutoff wavelength λc is a topic of widespread concern. In this paper, the method for improving λc by applying the regulation of the superconducting disorder is discussed, and a detector with an operating wavelength band of 5 - 10 μm is designed and fabricated. Studies have shown that the multiplication and diffusion behaviors of the quasiparticles always occur during the photon detection events, although the microscopic photodetection mechanism of SNSPD still lacks a perfect theoretical explanation. Therefore, the theoretical analysis mainly considers the influence of the quasiparticles in this paper, and the mathematical formula of the detection cutoff wavelength λc can be obtained based on the phenomenological quasiparticle diffusion model. Furthermore, the disorder-dependent superconducting phase transition temperature Tc, superconducting energy gap D, and electron thermalization time τth are also considered, in order to get more precise results.Theoretical analysis suggests that the increase in the sheet resistance Rs, which evaluates the disorder strength, will help to increase λc. For example, when the nanowire width is kept at 30 nm and Rs &gt; 380 Ω/□, it can be deduced that λc is larger than 10 μm.Experimentally, the active area of the device consists of a straight superconducting nanowire with a length of 10 μm and a width of 30 nm, so that it can effectively reduce the probability of the defects on the nanowire and avoid the current crowding effect. We have fabricated a 30 nm-wide Mo0.8Si0.2 mid infrared SNSPD, which has a cutoff wavelength λc no more than 5 μm, the effective strength of the disorder - the film sheet resistance Rs = 248.6 Ω/□. As a comparison, the sheet resistance, which is controlled by the film thickness, is increased to about 320 Ω/□ in this experiment.It is demonstrated that the Mo0.8Si0.2 detector with Rs ~320 Ω/□ can achieve saturated quantum efficiency at a wavelength of 6 μm. Furthermore, 53% quantum efficiency at the wavelength of 10.2 μm can be obtained when the detector works at a bias current of 0.9 ISW (ISW is the superconducting transition current), and it can theoretically reach a maximum value of 92% if the compression of switching current is excluded. Therefore, it can be predicted that the disorder regulation may become another efficient approach for designing high-performance mid-wave and long-wave infrared SNSPDs, in addition to the optimization of the superconducting energy gap and the cross section of superconducting nanowire.However, the continuous increase in the disorder will cause a d","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"85 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90589201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Deep Learning-Based Hole-Boring Radiation Pressure Ion Acceleration Modeling 基于深度学习的钻孔辐射压力离子加速建模
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230702
Zhang Pu-Du, Wang Wei-Quan, Li Zhe-Min, Zhang Zi-Xuan, Wang Ye-Chen, Zhou Hong-Yu, Yin Yan
Laser-driven ion acceleration has potential applications in high energy density matter, ion beam-driven fast ignition, beam target neutron source and warm dense matter heating and etc. Ultrashort relativistic lasers interacting with solid targets can generate ion beams with energies up to several hundreds of MeV, and the quality of the ion beams strongly depends on the interaction parameters of the laser and the targets. Developments in deep learning can provide new methods in the analysis of relationship between parameters in physics systems, which can significantly reduce the computational and experimental cost. In this paper, a continuous mapping model of ion peak and cutoff energies is developed based on a fully connected neural network(FCNN). In the model, the dataset is composed of nearly 400 sets of particle simulations of laser-driven solid targets, and the input parameters are laser intensity, target density, target thickness and ion mass. The model obtains the parameter analysis results in a large range of values with sparser parameter taking values, which greatly reduces the computational effort of sweeping the parameters in a large range of multi-dimensional parameters. Based on the results of this model mapping, the correction formula for the ion peak energy over ion mass is obtained. Furthermore, the ratio of ion cutoff energy and peak energy of each set of particle simulation is calculated. Repeating the same training process of ion peak energy and cutoff energy, the continuous mapping model of energy ratio is developed. According to the energy ratio model mapping results, the quantitative description of the relationship between ion cutoff energy and peak energy is realized, and the fitting formula for the cutoff energy of the Hole-Boring Radiation Pressure Acceleration (HB-RPA) mechanism is obtained, which can provide an important reference for the laser-driven ion acceleration experiments design.
激光驱动离子加速在高能密度物质、离子束驱动快速点火、束流靶中子源和热密度物质加热等方面具有潜在的应用前景。与固体目标相互作用的超短相对论激光器可以产生能量高达数百MeV的离子束,而离子束的质量很大程度上取决于激光器与目标的相互作用参数。深度学习的发展为物理系统中参数关系的分析提供了新的方法,大大降低了计算和实验成本。本文建立了基于全连接神经网络(FCNN)的离子峰值与截止能量的连续映射模型。在该模型中,数据集由近400组激光驱动固体目标的粒子模拟组成,输入参数为激光强度、目标密度、目标厚度和离子质量。该模型以更稀疏的参数取值获得大范围内的参数分析结果,大大减少了在大范围的多维参数范围内进行参数扫描的计算量。根据模型映射的结果,得到了离子峰值能量比离子质量的修正公式。此外,还计算了每组粒子模拟的离子截止能量与峰值能量之比。重复离子峰值能量和截止能量的相同训练过程,建立了能量比的连续映射模型。根据能量比模型映射结果,实现了离子截止能量与峰值能量关系的定量描述,得到了孔-钻孔辐射压力加速(HB-RPA)机制截止能量的拟合公式,可为激光驱动离子加速实验设计提供重要参考。
{"title":"Deep Learning-Based Hole-Boring Radiation Pressure Ion Acceleration Modeling","authors":"Zhang Pu-Du, Wang Wei-Quan, Li Zhe-Min, Zhang Zi-Xuan, Wang Ye-Chen, Zhou Hong-Yu, Yin Yan","doi":"10.7498/aps.72.20230702","DOIUrl":"https://doi.org/10.7498/aps.72.20230702","url":null,"abstract":"Laser-driven ion acceleration has potential applications in high energy density matter, ion beam-driven fast ignition, beam target neutron source and warm dense matter heating and etc. Ultrashort relativistic lasers interacting with solid targets can generate ion beams with energies up to several hundreds of MeV, and the quality of the ion beams strongly depends on the interaction parameters of the laser and the targets. Developments in deep learning can provide new methods in the analysis of relationship between parameters in physics systems, which can significantly reduce the computational and experimental cost. In this paper, a continuous mapping model of ion peak and cutoff energies is developed based on a fully connected neural network(FCNN). In the model, the dataset is composed of nearly 400 sets of particle simulations of laser-driven solid targets, and the input parameters are laser intensity, target density, target thickness and ion mass. The model obtains the parameter analysis results in a large range of values with sparser parameter taking values, which greatly reduces the computational effort of sweeping the parameters in a large range of multi-dimensional parameters. Based on the results of this model mapping, the correction formula for the ion peak energy over ion mass is obtained. Furthermore, the ratio of ion cutoff energy and peak energy of each set of particle simulation is calculated. Repeating the same training process of ion peak energy and cutoff energy, the continuous mapping model of energy ratio is developed. According to the energy ratio model mapping results, the quantitative description of the relationship between ion cutoff energy and peak energy is realized, and the fitting formula for the cutoff energy of the Hole-Boring Radiation Pressure Acceleration (HB-RPA) mechanism is obtained, which can provide an important reference for the laser-driven ion acceleration experiments design.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"26 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90636821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Synthesis and luminescent properties of rare earths doped Gd2Te4O11 tellurite phosphors 稀土掺杂Gd2Te4O11碲酸盐荧光粉的合成及其发光性能
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20221341
Luo Jie, Zhang Zi-Qiu, Xu Jun-Hao, Qin Zhao-Ting, Zhao Yuan-Shuai, He Hong, Li Guan-Nan, Tang Jian-Feng
A series of rare earth Dy3+, Tb3+, Eu3+ singly doped Gd2Te4O11 (GTO) tellurite phosphors with intrinsic polarity were prepared by hydrothermal method. The phase structure, morphology and thermal stability of the phosphors were characterized. Their luminescence properties were tested in detail. The results show all those phosphors were crystalized into single phase of digadolinium tellurite with short rod-like shape. The maximum size achieved microns in axial direction. The phosphors have good thermal stability. For the GTO:Dy3+, the fluorescence emission under UV excitation is mainly located in the yellow-green region. The optimal doping concentration corresponding to the strongest excitation and emission is 2.5%, and the CIE color coordinates are (0.39, 0.43). The fluorescence decay curves show that the lifetime of the GTO:Dy3+ on 4F9/2 energy level decreases gradually with increasing doping concentration of Dy3+, which may be related to the cross relaxation (CR) between Dy3+ ions. For the GTO:Eu3+, the fluorescence emission under UV excitation is mainly located in the red and orange-red regions. The emission intensity was enhanced with increasing doping concentration of Eu3+. When the doping concentration is 10%, the CIE color coordinates are (0.62, 0.38), which located in the orange-red region with high color purity. The fluorescence lifetime of Eu3+ on 5D0 energy level is hardly affected by the change of Eu3+ doping concentration. For the GTO:Tb3+, with increasing the Tb3+ concentration, the fluorescence emission under UV excitation changes from blue-violet region to yellow-green region, which can be ascribed to the influence of CR between Tb3+ ions. The fluorescence decay behavior revealed that the Tb3+ ions on 5D4 excited state may undergo energy transfer and reabsorption, which deviated fluorescence decay from the single exponential model. When the concentration of Tb3+ is 0.5%, the sample exhibits white light emission, having the CIE color coordinates of (0.33, 0.35) and color rendering index of 86. The measurements of temperature-dependent emission spectra show that the above-mentioned phosphors have good luminescent thermal stability. The internal quantum efficiencies (IQE) of those three types of phosphors were tested, and the IQE of GTO:Eu3+ are better than those of GTO:Dy3+ and GTO:Tb3+. All those phosphors still have much room for improvement in the luminescent performance. These phosphors have potential for the use of UV-excited white LED.
采用水热法制备了一系列稀土Dy3+、Tb3+、Eu3+单掺杂的GTO (Gd2Te4O11)碲酸盐本质极性荧光粉。表征了荧光粉的相结构、形貌和热稳定性。并对其发光性能进行了详细测试。结果表明,这些荧光粉均结晶为单相短棒状碲二adolinium。轴向最大尺寸达到微米级。该荧光粉具有良好的热稳定性。对于GTO:Dy3+,紫外激发下的荧光发射主要位于黄绿色区域。激发和发射最强对应的最佳掺杂浓度为2.5%,CIE色坐标为(0.39,0.43)。荧光衰减曲线显示,随着Dy3+掺杂浓度的增加,GTO:Dy3+在4F9/2能级上的寿命逐渐降低,这可能与Dy3+离子之间的交叉弛豫(CR)有关。对于GTO:Eu3+,紫外激发下的荧光发射主要位于红色和橙红色区域。发射强度随Eu3+掺杂浓度的增加而增强。当掺杂浓度为10%时,CIE色坐标为(0.62,0.38),位于橙色-红色区域,颜色纯度较高。Eu3+在5D0能级上的荧光寿命几乎不受Eu3+掺杂浓度变化的影响。对于GTO:Tb3+,随着Tb3+浓度的增加,紫外激发下的荧光发射由蓝紫色区变为黄绿色区,这可归因于Tb3+离子间CR的影响。荧光衰减行为表明,5D4激发态上的Tb3+离子可能发生能量转移和重吸收,偏离了单指数模型的荧光衰减。当Tb3+浓度为0.5%时,样品发出白光,CIE色坐标为(0.33,0.35),显色指数为86。温度依赖性发射光谱的测量表明,上述荧光粉具有良好的发光热稳定性。结果表明,GTO:Eu3+的内量子效率优于GTO:Dy3+和GTO:Tb3+的内量子效率。所有这些荧光粉在发光性能上仍有很大的改进空间。这些荧光粉有潜力用于紫外线激发的白光LED。
{"title":"Synthesis and luminescent properties of rare earths doped Gd2Te4O11 tellurite phosphors","authors":"Luo Jie, Zhang Zi-Qiu, Xu Jun-Hao, Qin Zhao-Ting, Zhao Yuan-Shuai, He Hong, Li Guan-Nan, Tang Jian-Feng","doi":"10.7498/aps.72.20221341","DOIUrl":"https://doi.org/10.7498/aps.72.20221341","url":null,"abstract":"A series of rare earth Dy<sup>3+</sup>, Tb<sup>3+</sup>, Eu<sup>3+</sup> singly doped Gd<sub>2</sub>Te<sub>4</sub>O<sub>11</sub> (GTO) tellurite phosphors with intrinsic polarity were prepared by hydrothermal method. The phase structure, morphology and thermal stability of the phosphors were characterized. Their luminescence properties were tested in detail. The results show all those phosphors were crystalized into single phase of digadolinium tellurite with short rod-like shape. The maximum size achieved microns in axial direction. The phosphors have good thermal stability. For the GTO:Dy<sup>3+</sup>, the fluorescence emission under UV excitation is mainly located in the yellow-green region. The optimal doping concentration corresponding to the strongest excitation and emission is 2.5%, and the CIE color coordinates are (0.39, 0.43). The fluorescence decay curves show that the lifetime of the GTO:Dy<sup>3+</sup> on <sup>4</sup>F<sub>9/2</sub> energy level decreases gradually with increasing doping concentration of Dy<sup>3+</sup>, which may be related to the cross relaxation (CR) between Dy<sup>3+</sup> ions. For the GTO:Eu<sup>3+</sup>, the fluorescence emission under UV excitation is mainly located in the red and orange-red regions. The emission intensity was enhanced with increasing doping concentration of Eu<sup>3+</sup>. When the doping concentration is 10%, the CIE color coordinates are (0.62, 0.38), which located in the orange-red region with high color purity. The fluorescence lifetime of Eu<sup>3+</sup> on <sup>5</sup>D<sub>0</sub> energy level is hardly affected by the change of Eu<sup>3+</sup> doping concentration. For the GTO:Tb<sup>3+</sup>, with increasing the Tb<sup>3+</sup> concentration, the fluorescence emission under UV excitation changes from blue-violet region to yellow-green region, which can be ascribed to the influence of CR between Tb<sup>3+</sup> ions. The fluorescence decay behavior revealed that the Tb<sup>3+</sup> ions on <sup>5</sup>D<sub>4</sub> excited state may undergo energy transfer and reabsorption, which deviated fluorescence decay from the single exponential model. When the concentration of Tb<sup>3+</sup> is 0.5%, the sample exhibits white light emission, having the CIE color coordinates of (0.33, 0.35) and color rendering index of 86. The measurements of temperature-dependent emission spectra show that the above-mentioned phosphors have good luminescent thermal stability. The internal quantum efficiencies (IQE) of those three types of phosphors were tested, and the IQE of GTO:Eu<sup>3+</sup> are better than those of GTO:Dy<sup>3+</sup> and GTO:Tb<sup>3+</sup>. All those phosphors still have much room for improvement in the luminescent performance. These phosphors have potential for the use of UV-excited white LED.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"10 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90822671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Phase separation in mixed systems of active particles with low and high inertia 低惯性和高惯性活性粒子混合体系的相分离
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230792
Wang Jing Jiao Yang Tian Wen-De Chen Kang, 焦阳, 田文得, 陈康
Active matter refers to a class of substances capable of autonomously moving by harnessing energy from their surrounding environment. These substances exhibit unique non-equilibrium phenomena, and hence have attracted great attention in the scientific community. Many active matters, such as bacteria, cells, micro-swimmers, and self-propelled colloidal particles, operate in viscous environment and their motions are usually described using overdamped models. Examples include overdamped active Brownian particle (ABP) model for self-propelled colloidal particles in solution and run-and-tumble (RTP) model for swimming bacteria. In recent years, increasing research studies have focused on the impact of inertia on the behavior of active matter. Vibrating robots, runners, flying insects, and micro-fliers are example active systems in the underdamped condition. The motion of these active matters can be modelled by underdamped Langevin equation, known as the active inertial particle (AIP) model. Previous studies have demonstrated that, similar to ABP systems, motility-induced phase separation (MIPS) phenomena also happen in AIP systems under certain density conditions. However, due to the strong collision-and-rebound effect, aggregation of AIP particles and hence the MIPS are impeded. In complex living/application environments, mixture of different active agents is often seen. Some studies on mixed systems of active matter show that the composition is an important quantity, influencing the phase separation phenomena. In this paper, we study the phase separation phenomena in mixed systems composed of low- and high-inertia active particles by underdamped Langevin dynamics simulations. We find that, compared to single-component system, the mixed systems are unexpectedly more favorable for the occurrence of phase separation at moderate overall concentration and certain range of component fraction, while more unfavorable for phase separation at high overall concentration. The underlying mechanism is that the presence of a small amount of the high-inertia particles could accelerate the motion of the low-inertia particles, and hence facilitate their aggregation and promote the phase separation. However, when the fraction of the high-inertia particles is large, frequent elastic collisions would disturb the aggregation of the low-inertia particles and suppress the occurrence of phase separation. Our results provide new sights into the collective behavior of active materials and also a reference for their design and applications.
活性物质是指一类能够利用周围环境的能量自主移动的物质。这些物质表现出独特的非平衡现象,因此引起了科学界的极大关注。许多活性物质,如细菌、细胞、微游泳者、自走胶体粒子等,都是在粘性环境中活动的,它们的运动通常用过阻尼模型来描述。例子包括溶液中自行式胶体粒子的过阻尼活性布朗粒子(ABP)模型和游动细菌的奔跑-翻滚(RTP)模型。近年来,越来越多的研究集中在惯性对活性物质行为的影响上。振动机器人、跑步者、飞虫和微型飞行器是欠阻尼条件下主动系统的例子。这些活性物质的运动可以用欠阻尼朗之万方程来模拟,称为活性惯性粒子(AIP)模型。先前的研究表明,与ABP体系类似,在一定密度条件下,AIP体系也会发生运动诱导相分离(MIPS)现象。然而,由于强烈的碰撞和反弹效应,AIP粒子的聚集受到阻碍,从而阻碍了MIPS。在复杂的生活/应用环境中,经常会看到不同活性剂的混合。对活性物质混合体系的一些研究表明,组分是影响相分离现象的一个重要量。本文通过欠阻尼朗之万动力学模拟,研究了由低惯性和高惯性活性粒子组成的混合系统中的相分离现象。我们发现,与单组分体系相比,混合体系意外地更有利于在中等总浓度和一定组分分数范围内发生相分离,而更不利于在高总浓度下发生相分离。其基本机制是少量高惯性粒子的存在可以加速低惯性粒子的运动,从而促进它们的聚集和相分离。然而,当高惯性粒子的比例较大时,频繁的弹性碰撞会干扰低惯性粒子的聚集,抑制相分离的发生。我们的研究结果为研究活性材料的集体行为提供了新的视角,也为活性材料的设计和应用提供了参考。
{"title":"Phase separation in mixed systems of active particles with low and high inertia","authors":"Wang Jing Jiao Yang Tian Wen-De Chen Kang, 焦阳, 田文得, 陈康","doi":"10.7498/aps.72.20230792","DOIUrl":"https://doi.org/10.7498/aps.72.20230792","url":null,"abstract":"Active matter refers to a class of substances capable of autonomously moving by harnessing energy from their surrounding environment. These substances exhibit unique non-equilibrium phenomena, and hence have attracted great attention in the scientific community. Many active matters, such as bacteria, cells, micro-swimmers, and self-propelled colloidal particles, operate in viscous environment and their motions are usually described using overdamped models. Examples include overdamped active Brownian particle (ABP) model for self-propelled colloidal particles in solution and run-and-tumble (RTP) model for swimming bacteria. In recent years, increasing research studies have focused on the impact of inertia on the behavior of active matter. Vibrating robots, runners, flying insects, and micro-fliers are example active systems in the underdamped condition. The motion of these active matters can be modelled by underdamped Langevin equation, known as the active inertial particle (AIP) model. Previous studies have demonstrated that, similar to ABP systems, motility-induced phase separation (MIPS) phenomena also happen in AIP systems under certain density conditions. However, due to the strong collision-and-rebound effect, aggregation of AIP particles and hence the MIPS are impeded. In complex living/application environments, mixture of different active agents is often seen. Some studies on mixed systems of active matter show that the composition is an important quantity, influencing the phase separation phenomena. In this paper, we study the phase separation phenomena in mixed systems composed of low- and high-inertia active particles by underdamped Langevin dynamics simulations. We find that, compared to single-component system, the mixed systems are unexpectedly more favorable for the occurrence of phase separation at moderate overall concentration and certain range of component fraction, while more unfavorable for phase separation at high overall concentration. The underlying mechanism is that the presence of a small amount of the high-inertia particles could accelerate the motion of the low-inertia particles, and hence facilitate their aggregation and promote the phase separation. However, when the fraction of the high-inertia particles is large, frequent elastic collisions would disturb the aggregation of the low-inertia particles and suppress the occurrence of phase separation. Our results provide new sights into the collective behavior of active materials and also a reference for their design and applications.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"26 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86842477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Composite Basis Set of Plane Wave and Gaussian Function or Spline Function 平面波与高斯函数或样条函数的复合基集
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230872
Zhang Guang-Di, Mao Li, Xu Hong-Xing
By combining plane waves with Gaussian or spline functions, this paper constructs a new composite basis set. As a non local basis vector, the plane wave basis group needs a large number of plane waves to expand all parts of the physical space, including the intermediate regions that are not important to our problems. Our basis set uses the local characteristics of Gaussian function or spline function at the same time, and controls the energy interval by selecting different plane wave vectors, so as to realize the partition solution of Hamiltonian matrix. Orthogonal normalization of composite basis sets is performed using Gram-Schmidt's orthogonalization method or Löwdin's orthogonalization method. Considering the completeness of plane wave vector, a certain value of positive and negative should be selected at the same time. Here, by changing the absolute value of wave vector, we can select the eigenvalue interval to be solved. The plane wave with a specific wave vector value is equivalent to a trial solution in the region with gentle potential energy. The algorithm automatically combines local Gaussian or spline functions to match the wave vector value difference between the trial solution and the strict solution. By selecting the absolute value of the wave vector in the plane wave function, this paper turns the calculation of large Hamiltonian matrices into the calculation of multiple small matrices, together with reducing the basis numbers in the region where the electron potential changes smoothly, we can significantly reduce the computational time. As an example, we apply this basis set to a one-dimensional finite depth potential well, it can be found that our method significantly reduce the number of basis vectors used to expand the wave function while maintaining a suitable degree of computational accuracy. We also studied the impact of different parameters on calculation accuracy. Finally, the above calculation method can be directly applied to the DFT calculation of plasmons in silver nanoplates or other metal nanostructures. Given a reasonable tentative initial state, the ground state electron density distribution of the system can be solved by self consistent solution using DFT theory, and then the electromagnetic field distribution and optical properties of the system can be solved using time-dependent density functional theory theory (TDDFT).
将平面波与高斯函数或样条函数结合,构造了一个新的复合基集。平面波基群作为非局部基向量,需要大量的平面波来扩展物理空间的各个部分,包括对我们的问题不重要的中间区域。我们的基集同时利用高斯函数或样条函数的局部特征,通过选择不同的平面波矢量来控制能量区间,从而实现哈密顿矩阵的分配解。复合基集的正交归一化采用Gram-Schmidt正交法或Löwdin正交法。考虑平面波矢量的完备性,应同时选取一定的正负值。在这里,通过改变波矢量的绝对值,我们可以选择待解的特征值区间。具有特定波矢值的平面波等效于具有弱势能区域的试解。该算法自动结合局部高斯函数或样条函数来匹配试解与严格解之间的波矢量值差。本文通过选取平面波函数中波矢量的绝对值,将大哈密顿矩阵的计算变为多个小矩阵的计算,同时减少电子势平稳变化区域的基数,可以显著减少计算时间。作为一个例子,我们将该基集应用于一维有限深度势井,可以发现我们的方法显着减少了用于展开波函数的基向量的数量,同时保持了适当的计算精度。研究了不同参数对计算精度的影响。最后,上述计算方法可直接应用于银纳米板或其他金属纳米结构中等离子体激元的DFT计算。给定合理的暂定初始态,利用DFT理论通过自洽解求解系统的基态电子密度分布,然后利用随时间密度泛函理论(TDDFT)求解系统的电磁场分布和光学性质。
{"title":"Composite Basis Set of Plane Wave and Gaussian Function or Spline Function","authors":"Zhang Guang-Di, Mao Li, Xu Hong-Xing","doi":"10.7498/aps.72.20230872","DOIUrl":"https://doi.org/10.7498/aps.72.20230872","url":null,"abstract":"By combining plane waves with Gaussian or spline functions, this paper constructs a new composite basis set. As a non local basis vector, the plane wave basis group needs a large number of plane waves to expand all parts of the physical space, including the intermediate regions that are not important to our problems. Our basis set uses the local characteristics of Gaussian function or spline function at the same time, and controls the energy interval by selecting different plane wave vectors, so as to realize the partition solution of Hamiltonian matrix. Orthogonal normalization of composite basis sets is performed using Gram-Schmidt's orthogonalization method or Löwdin's orthogonalization method. Considering the completeness of plane wave vector, a certain value of positive and negative should be selected at the same time. Here, by changing the absolute value of wave vector, we can select the eigenvalue interval to be solved. The plane wave with a specific wave vector value is equivalent to a trial solution in the region with gentle potential energy. The algorithm automatically combines local Gaussian or spline functions to match the wave vector value difference between the trial solution and the strict solution. By selecting the absolute value of the wave vector in the plane wave function, this paper turns the calculation of large Hamiltonian matrices into the calculation of multiple small matrices, together with reducing the basis numbers in the region where the electron potential changes smoothly, we can significantly reduce the computational time. As an example, we apply this basis set to a one-dimensional finite depth potential well, it can be found that our method significantly reduce the number of basis vectors used to expand the wave function while maintaining a suitable degree of computational accuracy. We also studied the impact of different parameters on calculation accuracy. Finally, the above calculation method can be directly applied to the DFT calculation of plasmons in silver nanoplates or other metal nanostructures. Given a reasonable tentative initial state, the ground state electron density distribution of the system can be solved by self consistent solution using DFT theory, and then the electromagnetic field distribution and optical properties of the system can be solved using time-dependent density functional theory theory (TDDFT).","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86919790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Channel processing-based time-reversal method for multi-target tunable focusing 基于信道处理的多目标可调聚焦时间反转方法
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230547
Chen Chuan-Sheng, Ding Shuai, Han Xu, Wang Bing-Zhong
Achieving tunable focus of electromagnetic field energy at multiple target points is a critical challenge in the wireless power transfer (WPT) domain. Although techniques such as optimal constrained power focusing (OCPF) and time reversal (TR) have been proposed. The former presents limited practical applicability while the latter is noteworthy for its adaptive spatio-temporal synchronous focusing characteristics. However, the time reversal mirror (TRM) method necessitates intricate pretesting and has highly complex systems. In this study, we introduce a novel channel processing method, named channel extraction, selection, weighting, and reconstruction (CESWR), to attain balanced power distribution for multiple users, characterized by low complexity, high computability, and rapid convergence. Diverging from the traditional TR approach, our proposed method, grounded in channel correlation considerations, filters the channel impulse response (CIR) for multiple targets, segregating them into distinct characteristic and similar components for each target. This method ensures focused generation at both receiving ends while facilitating high-precision regulation of the peak voltage of the received signal. Furthermore, this study embarks on a rigorous examination of the linearity intrinsic to the proposed methodology, explicating a singular correspondence between the tuning of theoretical weights and the resultant outcomes. In order to authenticate the efficacy of this methodology, we construct a single-input multiple-output time-reversal cavity (SIMO-TRC) system for the experimental section of this manuscript. Subsequent experimentation, conducted for both loosely and tightly correlated models, furnishes invaluable insights. Evidently, in the loosely correlated model, the CESWR method exhibits proficiency in attaining a peak voltage ratio (PVR) of nearly 1.00 at the two receivers, with a minuscule numerical discrepancy of merely 8×10-6 mV. In stark contrast, under the tightly correlated model, the CESWR method demonstrates an enhanced ability to differentiate between two targets, thus offering a noticeable improvement over the classic single-target TR method.
实现多目标点电磁场能量的可调聚焦是无线电力传输(WPT)领域的一个关键挑战。目前已经提出了最优约束功率聚焦(OCPF)和时间反转(TR)等技术。前者的实用性有限,而后者的自适应时空同步聚焦特性值得注意。然而,时间反转镜(TRM)方法需要复杂的预测试,并且具有高度复杂的系统。本文提出了一种新的信道处理方法,即信道提取、选择、加权和重构(CESWR),以实现多用户的均衡功率分配,具有低复杂度、高可计算性和快速收敛的特点。与传统的TR方法不同,本文提出的方法基于信道相关的考虑,对多个目标的信道脉冲响应(CIR)进行滤波,将每个目标的信道脉冲响应分离为特征不同和相似的分量。这种方法确保了在两个接收端集中产生,同时便于对接收信号的峰值电压进行高精度调节。此外,本研究开始对所提出的方法固有的线性进行严格检查,解释了理论权重调整与结果之间的奇异对应关系。为了验证这种方法的有效性,我们为本文的实验部分构建了一个单输入多输出时间反转腔(SIMO-TRC)系统。对松散和紧密相关的模型进行的后续实验提供了宝贵的见解。显然,在松散相关模型中,CESWR方法可以熟练地在两个接收器处获得接近1.00的峰值电压比(PVR),而数值差异仅为8×10-6 mV。与之形成鲜明对比的是,在紧密相关模型下,CESWR方法对两个目标的区分能力增强,与经典的单目标TR方法相比有了明显的改进。
{"title":"Channel processing-based time-reversal method for multi-target tunable focusing","authors":"Chen Chuan-Sheng, Ding Shuai, Han Xu, Wang Bing-Zhong","doi":"10.7498/aps.72.20230547","DOIUrl":"https://doi.org/10.7498/aps.72.20230547","url":null,"abstract":"Achieving tunable focus of electromagnetic field energy at multiple target points is a critical challenge in the wireless power transfer (WPT) domain. Although techniques such as optimal constrained power focusing (OCPF) and time reversal (TR) have been proposed. The former presents limited practical applicability while the latter is noteworthy for its adaptive spatio-temporal synchronous focusing characteristics. However, the time reversal mirror (TRM) method necessitates intricate pretesting and has highly complex systems. In this study, we introduce a novel channel processing method, named channel extraction, selection, weighting, and reconstruction (CESWR), to attain balanced power distribution for multiple users, characterized by low complexity, high computability, and rapid convergence. Diverging from the traditional TR approach, our proposed method, grounded in channel correlation considerations, filters the channel impulse response (CIR) for multiple targets, segregating them into distinct characteristic and similar components for each target. This method ensures focused generation at both receiving ends while facilitating high-precision regulation of the peak voltage of the received signal. Furthermore, this study embarks on a rigorous examination of the linearity intrinsic to the proposed methodology, explicating a singular correspondence between the tuning of theoretical weights and the resultant outcomes. In order to authenticate the efficacy of this methodology, we construct a single-input multiple-output time-reversal cavity (SIMO-TRC) system for the experimental section of this manuscript. Subsequent experimentation, conducted for both loosely and tightly correlated models, furnishes invaluable insights. Evidently, in the loosely correlated model, the CESWR method exhibits proficiency in attaining a peak voltage ratio (PVR) of nearly 1.00 at the two receivers, with a minuscule numerical discrepancy of merely 8×10-6 mV. In stark contrast, under the tightly correlated model, the CESWR method demonstrates an enhanced ability to differentiate between two targets, thus offering a noticeable improvement over the classic single-target TR method.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"18 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91294217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Molecular dynamics study of the effect of temperature on the shock response and plastic deformation mechanism of CoCrFeMnNi high-entropy alloys 温度对CoCrFeMnNi高熵合金冲击响应及塑性变形机制影响的分子动力学研究
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20221621
Wen Peng, Tao Gang
High-entropy alloys have broad application prospects in aviation,aerospace,military and other fields due to their excellent mechanical properties.Temperature is an important external factor affecting the shock response of high-entropy alloys.Molecular dynamics methods are used to investigate the effect of temperature on the shock response and plastic deformation mechanisms of CoCrFeMnNi high-entropy alloys.The effects of temperature on the atomic volume and the radial distribution function of CoCrFeMnNi high-entropy alloys are studied.Then,the piston method is used to generate shock waves in the sample to research the shock response of CoCrFeMnNi high-entropy alloys.The polyhedral template matching method is used to observe the evolution of atomic-scale defects during the shock compression.The results show that the shock pressure,the shock wave propagation velocity,and the shock-induced temperature rise decrease with the increase of the initial temperature.For example,when piston velocity Up=1.5 km/s,the shock pressure at an initial temperature of 1000 K decreased by 6.7% compared to that at 1 K.Moreover,the shock Hugoniot elastic limit decrease linearly with the increase of temperature.The Hugoniot Up- Us curve of CoCrFeMnNi HEA in the plastic stage can be linearly fitted by the formula Us=c0+sUp.c0 decreases with increasing temperature.With increasing shock intensities,CoCrFeMnNi high-entropy alloys undergo complex plastic deformation,including dislocation slip,phase transformation,deformation twinning,and shock-induced amorphization.At relatively high initial temperature,disordered clusters appear inside CoCrFeMnNi HEA,which together with the BCC structure transformed from FCC and disordered structure are significant dislocation nucleation sources.Compared with other elements,Mn element has the largest proportion (25.4%) in disordered clusters.Due to the large atomic volume and potential energy,large lattice distortion and local stress occur around the Mn-rich element,which provides dominant contribution to shock-induced plastic deformation.At high temperatures,the contribution of Fe element to plastic deformation is as important as that of Mn element.The research results contribute to a deep understanding of the shock-induced plasticity and deformation mechanisms of CoCrFeMnNi high-entropy alloys.
高熵合金以其优异的力学性能在航空、航天、军事等领域有着广阔的应用前景。温度是影响高熵合金冲击响应的重要外部因素。采用分子动力学方法研究了温度对CoCrFeMnNi高熵合金冲击响应和塑性变形机制的影响。研究了温度对CoCrFeMnNi高熵合金原子体积和径向分布函数的影响。然后,采用活塞法在试样中产生激波,研究CoCrFeMnNi高熵合金的冲击响应。采用多面体模板匹配方法观察了激波压缩过程中原子尺度缺陷的演化。结果表明:随着初始温度的升高,冲击压力、冲击波传播速度和冲击温升均呈下降趋势;例如,当活塞速度Up=1.5 km/s时,初始温度为1000 K时的冲击压力比初始温度为1 K时的冲击压力降低了6.7%。随着温度的升高,冲击Hugoniot弹性极限呈线性降低。CoCrFeMnNi HEA在塑性阶段的Hugoniot Up- Us曲线可以用公式Us=c0+sUp线性拟合。C0随温度升高而降低。随着冲击强度的增加,CoCrFeMnNi高熵合金发生复杂的塑性变形,包括位错滑移、相变、变形孪晶和冲击诱导非晶化。在较高的初始温度下,CoCrFeMnNi HEA内部出现无序团簇,这与FCC转变成的BCC结构和无序结构一起是位错成核的重要来源。与其他元素相比,Mn元素在无序簇中所占比例最大(25.4%)。由于大的原子体积和势能,富锰元素周围会发生大的晶格畸变和局部应力,这是造成冲击诱发塑性变形的主要原因。在高温下,铁元素对塑性变形的贡献与锰元素一样重要。研究结果有助于深入理解CoCrFeMnNi高熵合金的冲击诱发塑性和变形机理。
{"title":"Molecular dynamics study of the effect of temperature on the shock response and plastic deformation mechanism of CoCrFeMnNi high-entropy alloys","authors":"Wen Peng, Tao Gang","doi":"10.7498/aps.72.20221621","DOIUrl":"https://doi.org/10.7498/aps.72.20221621","url":null,"abstract":"High-entropy alloys have broad application prospects in aviation,aerospace,military and other fields due to their excellent mechanical properties.Temperature is an important external factor affecting the shock response of high-entropy alloys.Molecular dynamics methods are used to investigate the effect of temperature on the shock response and plastic deformation mechanisms of CoCrFeMnNi high-entropy alloys.The effects of temperature on the atomic volume and the radial distribution function of CoCrFeMnNi high-entropy alloys are studied.Then,the piston method is used to generate shock waves in the sample to research the shock response of CoCrFeMnNi high-entropy alloys.The polyhedral template matching method is used to observe the evolution of atomic-scale defects during the shock compression.The results show that the shock pressure,the shock wave propagation velocity,and the shock-induced temperature rise decrease with the increase of the initial temperature.For example,when piston velocity Up=1.5 km/s,the shock pressure at an initial temperature of 1000 K decreased by 6.7% compared to that at 1 K.Moreover,the shock Hugoniot elastic limit decrease linearly with the increase of temperature.The Hugoniot Up- Us curve of CoCrFeMnNi HEA in the plastic stage can be linearly fitted by the formula Us=c0+sUp.c0 decreases with increasing temperature.With increasing shock intensities,CoCrFeMnNi high-entropy alloys undergo complex plastic deformation,including dislocation slip,phase transformation,deformation twinning,and shock-induced amorphization.At relatively high initial temperature,disordered clusters appear inside CoCrFeMnNi HEA,which together with the BCC structure transformed from FCC and disordered structure are significant dislocation nucleation sources.Compared with other elements,Mn element has the largest proportion (25.4%) in disordered clusters.Due to the large atomic volume and potential energy,large lattice distortion and local stress occur around the Mn-rich element,which provides dominant contribution to shock-induced plastic deformation.At high temperatures,the contribution of Fe element to plastic deformation is as important as that of Mn element.The research results contribute to a deep understanding of the shock-induced plasticity and deformation mechanisms of CoCrFeMnNi high-entropy alloys.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"56 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73253429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Dependence of retrieval efficiency on the waist ratio of read beam and anti-Stokes photon modes in cavity-enhanced quantum memory 腔增强量子存储中读光束和反stokes光子模式腰比对检索效率的影响
IF 1 4区 物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY Pub Date : 2023-01-01 DOI: 10.7498/aps.72.20230966
Fan Wen-Xin, Wang Min-Jie, Jiao Hao-Le, Lu Jia-Jin, Liu Hai-Long, Yang Zhi-Fang, Xi Meng-Qi, Li Shu-Jing, Wang Hai
Quantum communication holds promise for absolutely secure information transmission. However, the direct transmission distance of quantum states is limited by the no-cloning theorem and transmission loss. To overcome these problems, Duan et al. proposed a promising quantum repeater scheme, DLCZ protocol (for Duan, Lukin, Cirac, and Zoller, in 2001), in which linear optics and atomic ensembles are used to combine entanglement generation and quantum memory into a single node. A quantum memory with highly retrieval efficiency is beneficial to increase the rate of entanglement swapping, achieving high-speed entanglement distribution. Up to now, high-efficiency quantum memories have been realized using high-optical-depth atomic ensembles or by coupling atomic ensembles with a medium-finesse optical cavity. However, the effect of the waist ratio of read beam and anti-Stokes photon modes on intrinsic retrieval efficiency has not been studied in detail. Here, we study the dependence of intrinsic retrieval efficiency on the waist ratio of read beam and anti-Stokes photon modes in cavity-enhanced quantum memory.In this work, a 87Rb atomic ensemble, that is placed at the center of a passively stabilized polarization interferometer (BD1,2), is used as quantum memory. Firstly, the ensemble is captured through magneto-optical trapping (MOT) and prepared to the Zeeman sub-level of ground state $|5{S_{1/2}},F = 1,m = 0rangle$. Then, a weak write pulse, with frequency red-detuned from the $|5{S_{1/2}},F = 1,m = 0rangle$$ to |5{P_{1/2}},F' = 1,m = 1rangle $ transition by 110 MHz, illuminates the atoms and induces spontaneous Raman scattering out a Stokes photon. In this regime of weak excitation, the detection of a Stokes photon heralds the storage of a single spin wave $|5{S_{1/2}},F = 1,m = 0rangle$$ leftrightarrow |5{S_{1/2}},F = 2,m = 0rangle $ ($|5{S_{1/2}},F = 1,m = 0rangle$$leftrightarrow |5{S_{1/2}},F = 2,m = 2rangle $) distributed among the whole ensemble. After a programmable delay, a read pulse, red-detuned from the $|5{S_{1/2}},F = 2,m = 0rangle to |5{P_{1/2}},F' = 2,m = - 1rangle $ transition by 110MHz, transfer this spin wave into an anti-Stokes photon. We detect the Stokes photons and anti-Stokes photons with polarization ${sigma ^ + }$, which means all the spin-wave are stored in a magnetic-field-insensitive state to reduce the decoherence caused by the stray magnetic fields. In order to increase the intrinsic retrieval efficiency, the atomic ensemble is placed in a ring cavity. The cavity length is 4 m, the finesse is measured to be ~15, and the escape efficiency of ring cavity is 52.9%. Both Stokes and anti-Stokes photon qubits are required to resonate with the ring cavity. To meet this requirement, a cavity-locking beam is injected into the cavity to stabilize the cavity length using a Pound-Drever-Hall locking scheme. Finally, we fixed the Stokes (anti-Stokes) photon modes waist and changed the waist ratio by changing the write beam (read beam)
量子通信有望实现绝对安全的信息传输。然而,量子态的直接传输距离受到不可克隆定理和传输损耗的限制。为了克服这些问题,Duan等人提出了一种很有前途的量子中继器方案,DLCZ协议(为Duan、Lukin、Cirac和Zoller于2001年提出),其中使用线性光学和原子系综将纠缠产生和量子存储结合到单个节点中。具有高检索效率的量子存储器有利于提高纠缠交换速率,实现高速纠缠分配。到目前为止,高效量子存储主要是利用高光深原子系综或将原子系综与中等精细度的光腔耦合实现的。然而,读光束和反斯托克斯光子模式腰比对本征检索效率的影响尚未得到详细的研究。本文研究了腔增强量子存储中读光束和反stokes光子模式腰比对本征检索效率的影响。在这项工作中,放置在被动稳定偏振干涉仪(BD1,2)中心的87Rb原子系综被用作量子存储器。首先,通过磁光捕获(MOT)捕获该系综,并将其制备到基态的塞曼亚能级$|5{S_{1/2}},F = 1,m = 0rangle$。然后,一个频率从$|5{S_{1/2}},F = 1,m = 0rangle$$ to |5{P_{1/2}},F' = 1,m = 1rangle $跃迁红失调谐110兆赫兹的弱写入脉冲,照亮原子并诱导自发拉曼散射出一个斯托克斯光子。在这种弱激发状态下,斯托克斯光子的探测预示着单个自旋波$|5{S_{1/2}},F = 1,m = 0rangle$$ leftrightarrow |5{S_{1/2}},F = 2,m = 0rangle $ ($|5{S_{1/2}},F = 1,m = 0rangle$$leftrightarrow |5{S_{1/2}},F = 2,m = 2rangle $)分布在整个系综中的存储。经过可编程延迟后,读取脉冲,从$|5{S_{1/2}},F = 2,m = 0rangle to |5{P_{1/2}},F' = 2,m = - 1rangle $跃迁红失调谐110MHz,将该自旋波转换为反斯托克斯光子。我们检测到Stokes光子和反Stokes光子的极化${sigma ^ + }$,这意味着所有的自旋波都以磁场不敏感的状态存储,以减少杂散磁场引起的退相干。为了提高本征检索效率,原子系综被放置在环形腔中。环形腔长度为4 m,精密度为15,环形腔的逃逸效率为52.9%. Both Stokes and anti-Stokes photon qubits are required to resonate with the ring cavity. To meet this requirement, a cavity-locking beam is injected into the cavity to stabilize the cavity length using a Pound-Drever-Hall locking scheme. Finally, we fixed the Stokes (anti-Stokes) photon modes waist and changed the waist ratio by changing the write beam (read beam) waist.The experiment result show that when the waist ratio of read beam and anti-Stokes photon modes is 3, the intrinsic retrieval efficiency is up to 68.9±1.6% and normalized cross-correlation function g(2) reaches 26.5±1.9. We built a theoretical model, the intrinsic retrieval efficiency increases with the rise of the waist ratio, which show that the intrinsic retrieval efficiency is up to the peak when the waist ratio is 3, and the intrinsic retrieval efficiency tends to be stable when the waist ratio continues to increase. The experiment agrees with the theory. In the future, we will improve the intrinsic retrieval efficiency by enhance the fineness of the optical cavity with optimizing the cavity parameters.
{"title":"Dependence of retrieval efficiency on the waist ratio of read beam and anti-Stokes photon modes in cavity-enhanced quantum memory","authors":"Fan Wen-Xin, Wang Min-Jie, Jiao Hao-Le, Lu Jia-Jin, Liu Hai-Long, Yang Zhi-Fang, Xi Meng-Qi, Li Shu-Jing, Wang Hai","doi":"10.7498/aps.72.20230966","DOIUrl":"https://doi.org/10.7498/aps.72.20230966","url":null,"abstract":"Quantum communication holds promise for absolutely secure information transmission. However, the direct transmission distance of quantum states is limited by the no-cloning theorem and transmission loss. To overcome these problems, Duan et al. proposed a promising quantum repeater scheme, DLCZ protocol (for Duan, Lukin, Cirac, and Zoller, in 2001), in which linear optics and atomic ensembles are used to combine entanglement generation and quantum memory into a single node. A quantum memory with highly retrieval efficiency is beneficial to increase the rate of entanglement swapping, achieving high-speed entanglement distribution. Up to now, high-efficiency quantum memories have been realized using high-optical-depth atomic ensembles or by coupling atomic ensembles with a medium-finesse optical cavity. However, the effect of the waist ratio of read beam and anti-Stokes photon modes on intrinsic retrieval efficiency has not been studied in detail. Here, we study the dependence of intrinsic retrieval efficiency on the waist ratio of read beam and anti-Stokes photon modes in cavity-enhanced quantum memory.In this work, a 87Rb atomic ensemble, that is placed at the center of a passively stabilized polarization interferometer (BD1,2), is used as quantum memory. Firstly, the ensemble is captured through magneto-optical trapping (MOT) and prepared to the Zeeman sub-level of ground state $|5{S_{1/2}},F = 1,m = 0rangle$. Then, a weak write pulse, with frequency red-detuned from the $|5{S_{1/2}},F = 1,m = 0rangle$$ to |5{P_{1/2}},F' = 1,m = 1rangle $ transition by 110 MHz, illuminates the atoms and induces spontaneous Raman scattering out a Stokes photon. In this regime of weak excitation, the detection of a Stokes photon heralds the storage of a single spin wave $|5{S_{1/2}},F = 1,m = 0rangle$$ leftrightarrow |5{S_{1/2}},F = 2,m = 0rangle $ ($|5{S_{1/2}},F = 1,m = 0rangle$$leftrightarrow |5{S_{1/2}},F = 2,m = 2rangle $) distributed among the whole ensemble. After a programmable delay, a read pulse, red-detuned from the $|5{S_{1/2}},F = 2,m = 0rangle to |5{P_{1/2}},F' = 2,m = - 1rangle $ transition by 110MHz, transfer this spin wave into an anti-Stokes photon. We detect the Stokes photons and anti-Stokes photons with polarization ${sigma ^ + }$, which means all the spin-wave are stored in a magnetic-field-insensitive state to reduce the decoherence caused by the stray magnetic fields. In order to increase the intrinsic retrieval efficiency, the atomic ensemble is placed in a ring cavity. The cavity length is 4 m, the finesse is measured to be ~15, and the escape efficiency of ring cavity is 52.9%. Both Stokes and anti-Stokes photon qubits are required to resonate with the ring cavity. To meet this requirement, a cavity-locking beam is injected into the cavity to stabilize the cavity length using a Pound-Drever-Hall locking scheme. Finally, we fixed the Stokes (anti-Stokes) photon modes waist and changed the waist ratio by changing the write beam (read beam) ","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"29 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72702810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
物理学报
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1