Active matter is a new and challenging field of physics. Chiral active particle experiences a constant torque and performs circular motion due to the self-propulsion force not aligning with the propulsion direction. Recently, most of studies of the active particle systems focused on constant temperature, but did not take into consideration the constraints by the barriers. In our work, the rectification of a ring containing chiral active particles with transversal temperature difference is numerically investigated in a two-dimensional periodic channel. It is found that the ring powered by chiral active particles can be rectified by the transversal temperature difference and the direction of the transport is determined by the chirality of active particles. The average velocity is a peaked function of angular velocity, the temperature of the lower wall or temperature difference. The transport behaviors of the ring containing one chiral active particle is qualitatively different from those of the ring containing several particles. Especially, the ring radius can strongly affect the transport behaviors. For the ring containing one chiral active particle, the interaction between the particle and the ring facilitates the rectification of the ring when the circular trajectory radius of the chiral particle is large. The average velocity decreases with the increase of the ring radius because the propelling force to the ring by the particle is small. When the circular trajectory radius is small, the interaction between the particle and the ring suppresses the transport. The speed increases as the ring radius increases because the directional transport comes from the difference in temperature between the upper wall and the lower wall. For the ring containing several particles, the interaction between particles reduces the rectification of the ring. The average velocity increases with the increase of the ring radius due to the interaction between particles decreasing. Remarkably, the velocity of the ring decreases as the particle number increases when the ring radius is small, but is a peaked function when the ring radius is not small. Our results offer new possibilities for manipulating an active particle flow on a microscale, and can be applied practically to propelling carriers and motors by a bath of bacteria or artificial microswimmers, such as hybrid micro-device engineering, drug delivery, micro-fluidics, and lab-on-chip technology.
{"title":"Transport of closed ring containing chiral active particles under transversal temperature difference","authors":"Jing-Jing Liao, Qi Kang, Fei Luo, Fu-Jun Lin","doi":"10.7498/aps.72.20221772","DOIUrl":"https://doi.org/10.7498/aps.72.20221772","url":null,"abstract":"Active matter is a new and challenging field of physics. Chiral active particle experiences a constant torque and performs circular motion due to the self-propulsion force not aligning with the propulsion direction. Recently, most of studies of the active particle systems focused on constant temperature, but did not take into consideration the constraints by the barriers. In our work, the rectification of a ring containing chiral active particles with transversal temperature difference is numerically investigated in a two-dimensional periodic channel. It is found that the ring powered by chiral active particles can be rectified by the transversal temperature difference and the direction of the transport is determined by the chirality of active particles. The average velocity is a peaked function of angular velocity, the temperature of the lower wall or temperature difference. The transport behaviors of the ring containing one chiral active particle is qualitatively different from those of the ring containing several particles. Especially, the ring radius can strongly affect the transport behaviors. For the ring containing one chiral active particle, the interaction between the particle and the ring facilitates the rectification of the ring when the circular trajectory radius of the chiral particle is large. The average velocity decreases with the increase of the ring radius because the propelling force to the ring by the particle is small. When the circular trajectory radius is small, the interaction between the particle and the ring suppresses the transport. The speed increases as the ring radius increases because the directional transport comes from the difference in temperature between the upper wall and the lower wall. For the ring containing several particles, the interaction between particles reduces the rectification of the ring. The average velocity increases with the increase of the ring radius due to the interaction between particles decreasing. Remarkably, the velocity of the ring decreases as the particle number increases when the ring radius is small, but is a peaked function when the ring radius is not small. Our results offer new possibilities for manipulating an active particle flow on a microscale, and can be applied practically to propelling carriers and motors by a bath of bacteria or artificial microswimmers, such as hybrid micro-device engineering, drug delivery, micro-fluidics, and lab-on-chip technology.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"36 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90805052","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}
Facing with the increasing capacity requirements of on-chip optical interconnects, mode division multiplexing technology (MDM), which leverages the different spatial eigenmodes at the same wavelength as independent channels to transmit optical signals, has attracted tremendous interest. Mode-order converters that can convert the fundamental mode to high-order modes are key components in MDM systems. However, it is still very challenging to achieve compact mode-order converters with high performances. Subwavelength grating (SWG) can be equivalent to homogenous material, which has the prominent advantages such as control over birefringence, dispersion and anisotropy, enabling photonic devices with high performance. Wheras the conventional SWG only needs single-etch step, but the implementation of SWG structure usually requires a fabrication resolution of the order of 100 nm and below, which is difficult for current wafer-scale fabrication technology. The anisotropic response of SWG can be further engineered by introducing bricked topology structure, providing an additional degree of freedom in the design. Meanwhile, the requirement of fabrication resolution can also be reduced (>100 nm). In this work, we experimentally demonstrate compact TE0-TE1 and TE0-TE2 mode-order converters using bricked subwavelength grating (BSWG) based on silicon-on-insulator (SOI) with the minimum feature size of the BSWG is 145 nm. In the proposed mode-order converter, a quasi-TE0 mode is generated in the BSWG region, which can be regarded as an effective bridge between the two TE modes to be converted. Flexible mode conversion can be realized by only choosing appropriate structural parameters for specific mode transitions between input/output modes and the quasi-TE0 mode. By combing 3D finite difference time domain (FDTD) and particle swarm optimization (PSO) method, TE0-TE1 and TE0-TE2 mode-order converters are optimal designed. It can convert TE0 mode into TE1 and TE2 mode with conversion length of 9.39 μm and 11.27 μm. The simulation results show that the insertion loss of <1 dB and crosstalk of < ‒ 15 dB are achieved for both TE0-TE1 and TE0-TE2 mode-order converters, the corresponding working bandwidth are 128 nm (1511~1639 nm) and 126 nm (1527~1653 nm), respectively. The measurement results indicate that insertion loss and crosstalk are less than 2.5 dB and -10 dB in a bandwidth of 68 nm (1512~1580 nm, limited by the laser tuning range and grating coupler).
{"title":"A compact silicon-based mode converter using bricked subwavelength grating","authors":"Lu Meng-jia, Yun Bin-Feng","doi":"10.7498/aps.72.20230673","DOIUrl":"https://doi.org/10.7498/aps.72.20230673","url":null,"abstract":"Facing with the increasing capacity requirements of on-chip optical interconnects, mode division multiplexing technology (MDM), which leverages the different spatial eigenmodes at the same wavelength as independent channels to transmit optical signals, has attracted tremendous interest. Mode-order converters that can convert the fundamental mode to high-order modes are key components in MDM systems. However, it is still very challenging to achieve compact mode-order converters with high performances. Subwavelength grating (SWG) can be equivalent to homogenous material, which has the prominent advantages such as control over birefringence, dispersion and anisotropy, enabling photonic devices with high performance. Wheras the conventional SWG only needs single-etch step, but the implementation of SWG structure usually requires a fabrication resolution of the order of 100 nm and below, which is difficult for current wafer-scale fabrication technology. The anisotropic response of SWG can be further engineered by introducing bricked topology structure, providing an additional degree of freedom in the design. Meanwhile, the requirement of fabrication resolution can also be reduced (>100 nm). In this work, we experimentally demonstrate compact TE0-TE1 and TE0-TE2 mode-order converters using bricked subwavelength grating (BSWG) based on silicon-on-insulator (SOI) with the minimum feature size of the BSWG is 145 nm. In the proposed mode-order converter, a quasi-TE0 mode is generated in the BSWG region, which can be regarded as an effective bridge between the two TE modes to be converted. Flexible mode conversion can be realized by only choosing appropriate structural parameters for specific mode transitions between input/output modes and the quasi-TE0 mode. By combing 3D finite difference time domain (FDTD) and particle swarm optimization (PSO) method, TE0-TE1 and TE0-TE2 mode-order converters are optimal designed. It can convert TE0 mode into TE1 and TE2 mode with conversion length of 9.39 μm and 11.27 μm. The simulation results show that the insertion loss of <1 dB and crosstalk of < ‒ 15 dB are achieved for both TE0-TE1 and TE0-TE2 mode-order converters, the corresponding working bandwidth are 128 nm (1511~1639 nm) and 126 nm (1527~1653 nm), respectively. The measurement results indicate that insertion loss and crosstalk are less than 2.5 dB and -10 dB in a bandwidth of 68 nm (1512~1580 nm, limited by the laser tuning range and grating coupler).","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"59 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90868198","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}
Graphene-based van der Waals heterojunctions can not only modulate the electronic properties of graphene but also retain the superior properties of the original monolayer. In this paper, the structure, electrical contact types, electronic and optical properties of Graphene/C3N van der Waals heterojunctions are systematically investigated based on first-principles calculations. We find that there is a p-type Schottky contact of only 0.039 eV in the Graphene/C3N van der Waals heterojunctions at the equilibrium state. The external electric field can adjust the interface contact type, from p-type to n-type schottky contact, or from p-type schottky contact to ohmic contact. The vertical strain not only opens a nonnegligible band gap of 360 meV at the Dirac cone of Graphene in Graphene/C3N van der Waals heterojunctions, but also modulates the band gap of C3N in the heterojunctions. Moreover, both the doping type and concentration of the carrier can be effectively tuned by the applied electric field and the vertical strain. The increase in carrier concentration is more pronounced by the applied electric field. Compared with the pristine monolayer Graphene and monolayer C3N, the optical response range and the light absorption rate of Graphene/C3N van der Waals heterojunctions are enhanced. Main absorption peak in the spectrum up to 106 cm-1. These results not only provide valuable theoretical guidance for the design of Schottky-based Graphene/C3N van der Waals heterojunctions devices, but also further explore the potential of heterojunctions for further applications in optoelectronic nanodevices and field-effect transistor devices.
石墨烯基范德华异质结不仅可以调制石墨烯的电子特性，还可以保留原有单层石墨烯的优越性能。本文基于第一性原理计算系统地研究了石墨烯/C3N范德华异质结的结构、电接触类型、电子和光学性质。我们发现石墨烯/C3N范德华异质结在平衡状态下存在一个p型肖特基接触，只有0.039 eV。外加电场可以调节界面接触类型，从p型肖特基接触到n型肖特基接触，或从p型肖特基接触到欧姆接触。在石墨烯/C3N范德华异质结中，垂直应变不仅在石墨烯的狄拉克锥上打开了一个不可忽略的360 meV带隙，而且还调节了C3N在异质结中的带隙。此外，外加电场和垂直应变可以有效地调节载流子的掺杂类型和浓度。外加电场使载流子浓度的增加更为明显。与原始单层石墨烯和单层C3N相比，石墨烯/C3N van der Waals异质结的光响应范围和光吸收率都有所提高。光谱中主要吸收峰高达106 cm-1。这些结果不仅为基于schottkey的石墨烯/C3N范德华异质结器件的设计提供了有价值的理论指导，而且进一步探索了异质结在光电纳米器件和场效应晶体管器件中的进一步应用潜力。
{"title":"Tunable electronic structures and interface contact in graphene/C3N van der Waals heterostructures","authors":"Huang Min, Li ZhanHai, Cheng Fang","doi":"10.7498/aps.72.20230318","DOIUrl":"https://doi.org/10.7498/aps.72.20230318","url":null,"abstract":"Graphene-based van der Waals heterojunctions can not only modulate the electronic properties of graphene but also retain the superior properties of the original monolayer. In this paper, the structure, electrical contact types, electronic and optical properties of Graphene/C3N van der Waals heterojunctions are systematically investigated based on first-principles calculations. We find that there is a p-type Schottky contact of only 0.039 eV in the Graphene/C3N van der Waals heterojunctions at the equilibrium state. The external electric field can adjust the interface contact type, from p-type to n-type schottky contact, or from p-type schottky contact to ohmic contact. The vertical strain not only opens a nonnegligible band gap of 360 meV at the Dirac cone of Graphene in Graphene/C3N van der Waals heterojunctions, but also modulates the band gap of C3N in the heterojunctions. Moreover, both the doping type and concentration of the carrier can be effectively tuned by the applied electric field and the vertical strain. The increase in carrier concentration is more pronounced by the applied electric field. Compared with the pristine monolayer Graphene and monolayer C3N, the optical response range and the light absorption rate of Graphene/C3N van der Waals heterojunctions are enhanced. Main absorption peak in the spectrum up to 106 cm-1. These results not only provide valuable theoretical guidance for the design of Schottky-based Graphene/C3N van der Waals heterojunctions devices, but also further explore the potential of heterojunctions for further applications in optoelectronic nanodevices and field-effect transistor devices.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"84 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74567220","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}
Wang Li-na, Chen Li, Sheng Min-Jia, Wang Lei-Lei, Cui Hai-Hang, Zheng Xu, Huang Min-Hua
Self-propelled micromotors serve as a bridge between the microfluidic environments and macroscopic control. They have broad application prospects in targeted drug delivery, biosensors, and other fields. The high driving speed of bubble micromotors is an irreplaceable advantage in practical applications. Bubble micromotors convert chemical energy in ambient solutions into mechanical energy through asymmetric surface catalytic reactions to drive their own motion. The energy conversion rate of bubble driving is used as an indicator to evaluate the driving force. The Pt catalytic layer of a tubular micromotor is located on the inner wall of the microtube. Bubbles form inside the tube. It is released from one end of the microtubule into the solution and self driven by bubble rebound, with an energy conversion rate of ~10-10. The Janus microsphere motor near the gas-liquid interface utilizes the energy of the bubble coalesced with the interface to drive the microsphere, with an energy conversion rate of ~10-7. In sum, the tubular bubble motor is suitable for complex scenarios but has low energy conversion rate. The Janus microsphere motor driven by bubbles has high efficiency but is only suitable near the gas-liquid interface. This paper combines the advantages of driving tubular micromotors in bulk solution and Janus microsphere motors utilizing interface energy to efficiently drive, proposing a new method of dual bubble coalescence and driving Janus microsphere motors. In the experiment, a high-speed camera was used to record the ~100μs of dual bubble coalescence and the process of driving micromotors. Then we investigates the initial kinetic energy conversion rate of micro motors driven by bubble coalescence. Three sets of different bubble/particle size ratios of Rb/Rp<1, Rb/Rp≈1, Rb/Rp>1 were presented for their propulsion effects on microspheres. The initial kinetic energy conversion rate was defined to characterize the contribution of bubble coalescence process to microsphere driving. After simulations with the pseudo potential lattice Boltzmann method, the mechanism of bubble coalescence driving the motion of microspheres was revealed. It is clarified that the interface oscillation caused by bubble coalescence is the main reason driving the micromotor, and its energy conversion rate is between the rebound driving of the tubular micromotor and the one-bubble coalescence driving with the freesurface. The research results revealed the details of bubble coalescence at different time periods, and provided the effects of factors such as bubble particle size ratio on microsphere displacement and initial kinetic energy conversion rate. It confirmed the efficient driving mechanism of dual bubble coalescence and release of surface energy.
{"title":"Study on the mechanism of the interface evolution of dual-bubble coalescence driving micromotors in bulk phase","authors":"Wang Li-na, Chen Li, Sheng Min-Jia, Wang Lei-Lei, Cui Hai-Hang, Zheng Xu, Huang Min-Hua","doi":"10.7498/aps.72.20230608","DOIUrl":"https://doi.org/10.7498/aps.72.20230608","url":null,"abstract":"Self-propelled micromotors serve as a bridge between the microfluidic environments and macroscopic control. They have broad application prospects in targeted drug delivery, biosensors, and other fields. The high driving speed of bubble micromotors is an irreplaceable advantage in practical applications. Bubble micromotors convert chemical energy in ambient solutions into mechanical energy through asymmetric surface catalytic reactions to drive their own motion. The energy conversion rate of bubble driving is used as an indicator to evaluate the driving force. The Pt catalytic layer of a tubular micromotor is located on the inner wall of the microtube. Bubbles form inside the tube. It is released from one end of the microtubule into the solution and self driven by bubble rebound, with an energy conversion rate of ~10-10. The Janus microsphere motor near the gas-liquid interface utilizes the energy of the bubble coalesced with the interface to drive the microsphere, with an energy conversion rate of ~10-7. In sum, the tubular bubble motor is suitable for complex scenarios but has low energy conversion rate. The Janus microsphere motor driven by bubbles has high efficiency but is only suitable near the gas-liquid interface. This paper combines the advantages of driving tubular micromotors in bulk solution and Janus microsphere motors utilizing interface energy to efficiently drive, proposing a new method of dual bubble coalescence and driving Janus microsphere motors. In the experiment, a high-speed camera was used to record the ~100μs of dual bubble coalescence and the process of driving micromotors. Then we investigates the initial kinetic energy conversion rate of micro motors driven by bubble coalescence. Three sets of different bubble/particle size ratios of Rb/Rp<1, Rb/Rp≈1, Rb/Rp>1 were presented for their propulsion effects on microspheres. The initial kinetic energy conversion rate was defined to characterize the contribution of bubble coalescence process to microsphere driving. After simulations with the pseudo potential lattice Boltzmann method, the mechanism of bubble coalescence driving the motion of microspheres was revealed. It is clarified that the interface oscillation caused by bubble coalescence is the main reason driving the micromotor, and its energy conversion rate is between the rebound driving of the tubular micromotor and the one-bubble coalescence driving with the freesurface. The research results revealed the details of bubble coalescence at different time periods, and provided the effects of factors such as bubble particle size ratio on microsphere displacement and initial kinetic energy conversion rate. It confirmed the efficient driving mechanism of dual bubble coalescence and release of surface energy.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"87 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74570052","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}
Yuan Yang, Naifang Hu, Yongcheng Jin, Jun Ma, Guanglei Cui
The development of all-solid-state lithium batteries with high energy density, long cycle life, low cost and high safety is one of the important directions for the development of next-generation lithium-ion batteries. Lithium-rich cathode materials have been widely used in liquid lithium batteries for their higher discharge specific capacity (> 250 mAh g-1) and energy density (> 900 Wh kg-1), due to the synergistic redox of anions and cations, as well as their high thermal stability and low raw material cost. With the rapid development of high-performance lithium-rich cathode materials and solid-state electrolytes in all-solid-state lithium batteries, the application of lithium-rich cathode materials in all-solid-state lithium batteries is expected to break through to the target of 500 W h kg-1 energy density of lithium-ion batteries. In this review, we firstly elaborate the failure mechanism of lithium-rich cathode materials in all-solid-state lithium batteries. The poor electronic conductivity, irreversible redox reaction of anionic oxygen and structute transformation during the electrochemical cycling of lithium-rich cathode materials lead to the low initial coulomb efficiency, poor cycling stability and voltage decay. In addition, the high operating voltage of lithium-rich cathode materials (> 4.5 V vs. Li/Li+) exposes the cathode/electrolyte to not only conventional interfacial chemical reactions, but the released oxygen also aggravates the interfacial electrochemical reactions, which put higher demands on the interfacial stability of the cathode/electrolyte. Therefore, the intrinsic characteristics of lithium-rich cathode materials and the severe interfacial reaction of lithium-rich cathode/electrolyte greatly limit the application of lithium-rich cathode materials in all-solid-state lithium batteries. Then, we review the research progress of lithium-rich cathode materials in various solid-state electrolyte systems in recent years. The higher room temperature ionic conductivity and wider voltage window of inorganic solid-state electrolytes provide opportunities for the application of lithium-rich cathode materials in all-solid-state lithium batteries. At present, the application of lithium-rich cathode materials in all-solid-state lithium batteries has been initially explored on the basis of sulfide, halide and oxide solid-state electrolyte systems, and important progress has been made in studies including composite cathode preparation methods, interfacial reaction mechanisms and activation mechanisms. Finally, we summarize the current research focus of lithium-rich cathode all-solid-state lithium batteries and propose several strategies for their future outlook. Strategies such as the regulation of cathode material components, the construction of lithium ion and electron transport pathways within the composite cathode, and the interfacial modification of cathode materials have been shown to have significant effects in solving the failure p
开发高能量密度、长循环寿命、低成本、高安全性的全固态锂电池是下一代锂离子电池发展的重要方向之一。富锂正极材料由于阴离子和阳离子的协同氧化还原作用，具有较高的放电比容量(> 250mah g-1)和能量密度(> 900wh kg-1)，以及较高的热稳定性和较低的原料成本，已广泛应用于液体锂电池中。随着全固态锂电池中高性能富锂正极材料和固态电解质的快速发展，全固态锂电池中富锂正极材料的应用有望突破到锂离子电池500w h kg-1能量密度的目标。本文首先阐述了全固态锂电池中富锂正极材料的失效机理。富锂正极材料在电化学循环过程中的电子导电性差、阴离子氧不可逆氧化还原反应和结构转变导致其初始库仑效率低、循环稳定性差和电压衰减。此外，富锂正极材料的高工作电压(> 4.5 V vs. Li/Li+)不仅使阴极/电解液暴露在常规的界面化学反应中，而且释放的氧气也加剧了界面电化学反应，这对阴极/电解液的界面稳定性提出了更高的要求。因此，富锂正极材料的固有特性和富锂正极/电解质剧烈的界面反应极大地限制了富锂正极材料在全固态锂电池中的应用。综述了近年来在各种固态电解质体系中富锂正极材料的研究进展。无机固态电解质具有较高的室温离子电导率和较宽的电压窗，为富锂正极材料在全固态锂电池中的应用提供了机会。目前，在硫化物、卤化物、氧化物固态电解质体系的基础上，对富锂正极材料在全固态锂电池中的应用进行了初步探索，在复合正极制备方法、界面反应机理、活化机理等方面的研究都取得了重要进展。最后，总结了目前富锂阴极全固态锂电池的研究热点，并对其未来前景提出了几点展望。阴极材料组分的调控、复合阴极内锂离子和电子传递路径的构建、阴极材料界面的修饰等策略已被证明对解决失效问题有显著效果。
{"title":"Advance of lithium-rich cathode materials in all-solid-state lithium batteries","authors":"Yuan Yang, Naifang Hu, Yongcheng Jin, Jun Ma, Guanglei Cui","doi":"10.7498/aps.72.20230258","DOIUrl":"https://doi.org/10.7498/aps.72.20230258","url":null,"abstract":"The development of all-solid-state lithium batteries with high energy density, long cycle life, low cost and high safety is one of the important directions for the development of next-generation lithium-ion batteries. Lithium-rich cathode materials have been widely used in liquid lithium batteries for their higher discharge specific capacity (> 250 mAh g-1) and energy density (> 900 Wh kg-1), due to the synergistic redox of anions and cations, as well as their high thermal stability and low raw material cost. With the rapid development of high-performance lithium-rich cathode materials and solid-state electrolytes in all-solid-state lithium batteries, the application of lithium-rich cathode materials in all-solid-state lithium batteries is expected to break through to the target of 500 W h kg-1 energy density of lithium-ion batteries. In this review, we firstly elaborate the failure mechanism of lithium-rich cathode materials in all-solid-state lithium batteries. The poor electronic conductivity, irreversible redox reaction of anionic oxygen and structute transformation during the electrochemical cycling of lithium-rich cathode materials lead to the low initial coulomb efficiency, poor cycling stability and voltage decay. In addition, the high operating voltage of lithium-rich cathode materials (> 4.5 V vs. Li/Li+) exposes the cathode/electrolyte to not only conventional interfacial chemical reactions, but the released oxygen also aggravates the interfacial electrochemical reactions, which put higher demands on the interfacial stability of the cathode/electrolyte. Therefore, the intrinsic characteristics of lithium-rich cathode materials and the severe interfacial reaction of lithium-rich cathode/electrolyte greatly limit the application of lithium-rich cathode materials in all-solid-state lithium batteries. Then, we review the research progress of lithium-rich cathode materials in various solid-state electrolyte systems in recent years. The higher room temperature ionic conductivity and wider voltage window of inorganic solid-state electrolytes provide opportunities for the application of lithium-rich cathode materials in all-solid-state lithium batteries. At present, the application of lithium-rich cathode materials in all-solid-state lithium batteries has been initially explored on the basis of sulfide, halide and oxide solid-state electrolyte systems, and important progress has been made in studies including composite cathode preparation methods, interfacial reaction mechanisms and activation mechanisms. Finally, we summarize the current research focus of lithium-rich cathode all-solid-state lithium batteries and propose several strategies for their future outlook. Strategies such as the regulation of cathode material components, the construction of lithium ion and electron transport pathways within the composite cathode, and the interfacial modification of cathode materials have been shown to have significant effects in solving the failure p","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"80 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74667346","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}
Non-carrier-injection light-emitting diodes (NCI-LEDs) are expected to be widely used in next generation micro-display technologies, including Micro-LEDs and nano-pixel light-emitting displays due to their simple device structure. However, because there is no charge carrier injection from external electrodes, carrier transport behavior of the NCI-LED cannot be described by using the traditional PN junction and LED theory. Therefore, establishing a carrier-transport model for the NCI-LED is of great significance for understanding its working mechanism and for improving device performance. In this paper, carrier transport mathematical model of the NCI-LED is established and the mechanical behavior of charge-carrier transport is analyzed quantitatively. Based on the mathematical model, the working mechanism of the NCI-LED is explained, the carrier transport characteristics of the device are obtained. Additionally, the key features, including the length of the induced charge region, the forward biased voltage across the internal PN junction, and the reverse biased voltage across the internal PN junction are studied. Their relationships with the applied frequency of the applied driving voltage are revealed. It is found that both the forward and reverse biases of the internal PN junction increase with the driving frequency. When the driving frequency reaches a certain value, the forward and reverse bias of the PN junction would be maintained at a maximum value. Moreover, the length of the induced charge region decreases with the increase of the driving frequency, and when the frequency reaches a certain value, the induced charge region would always be in the state of exhaustion. According to the mathematical model, suggestions for the device optimization design are provided: (1) Reducing the doping concentration of the induced charge regions can effectively increase the voltage drop across the internal LED; (2) Employing the tunneling effect occurring in the reverse-biased PN junction can effectively improve the electroluminescence intensity; (3) Using square-wave driving voltage can obtain a larger voltage drop across the internal LED and increase the electroluminescence intensity. This work on the carrier transport model is expected to provide a clear physical image for understanding the working mechanism of NCI-LED, and to provide a theoretical guidance for optimizing the device structure.
{"title":"Carrier Transport Model of Non-carrier-injection LED","authors":"Zhao Jian-Cheng, Wu Chao-Xing, Guo Tai-Liang","doi":"10.7498/aps.72.20221831","DOIUrl":"https://doi.org/10.7498/aps.72.20221831","url":null,"abstract":"Non-carrier-injection light-emitting diodes (NCI-LEDs) are expected to be widely used in next generation micro-display technologies, including Micro-LEDs and nano-pixel light-emitting displays due to their simple device structure. However, because there is no charge carrier injection from external electrodes, carrier transport behavior of the NCI-LED cannot be described by using the traditional PN junction and LED theory. Therefore, establishing a carrier-transport model for the NCI-LED is of great significance for understanding its working mechanism and for improving device performance. In this paper, carrier transport mathematical model of the NCI-LED is established and the mechanical behavior of charge-carrier transport is analyzed quantitatively. Based on the mathematical model, the working mechanism of the NCI-LED is explained, the carrier transport characteristics of the device are obtained. Additionally, the key features, including the length of the induced charge region, the forward biased voltage across the internal PN junction, and the reverse biased voltage across the internal PN junction are studied. Their relationships with the applied frequency of the applied driving voltage are revealed. It is found that both the forward and reverse biases of the internal PN junction increase with the driving frequency. When the driving frequency reaches a certain value, the forward and reverse bias of the PN junction would be maintained at a maximum value. Moreover, the length of the induced charge region decreases with the increase of the driving frequency, and when the frequency reaches a certain value, the induced charge region would always be in the state of exhaustion. According to the mathematical model, suggestions for the device optimization design are provided: (1) Reducing the doping concentration of the induced charge regions can effectively increase the voltage drop across the internal LED; (2) Employing the tunneling effect occurring in the reverse-biased PN junction can effectively improve the electroluminescence intensity; (3) Using square-wave driving voltage can obtain a larger voltage drop across the internal LED and increase the electroluminescence intensity. This work on the carrier transport model is expected to provide a clear physical image for understanding the working mechanism of NCI-LED, and to provide a theoretical guidance for optimizing the device structure.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"20 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74763898","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}
Wang Yue, Wang Lun, Sun Baixun, Lang Peng, Xu Yang, Zhao Zhenlong, Song Xiaowei, Ji Boyu, Lin Jingquan
Localized Surface Plasmon (LSP) in nanostructure excited by Surface Plasmon Polariton (SPP) corresponds to stronger near-field enhancement and special spectral and dynamic responses that provides a new path to explore the interaction between light and matter. Meanwhile, this scheme can also release the signal background noise and structural thermal effect, and improve the performance of plasmonic components and sensing detectors based on LSP. However, the current research on this aspect is still insufficient. In this paper, we investigated the near-field characteristics of a plasmon composite structure composed of plasmon focusing lens and gold nanorod under the excitation of dual-beam using Finite-Difference Time-Domain (FDTD) method. The result shows that the near-field intensity control on the upper surface and in the gap position of the nanorod can be achieved by adjusting the relative time delay between the first light beam (used to excite SPP) and the second light beam (used to excite LSP). Specifically, the maximum adjustment range of the near-field intensity corresponding to 770 nm resonant mode in the gap position is about 23, and the adjustment period is about 2.4 fs. In a resonant mode dominated by SPP at a wavelength of 999 nm, the near-field intensity adjustment range is as small as 6, and the adjustment period is about 4 fs. On the upper surface of the structure, the adjustment range of the near-field intensity of the two resonant modes (719 nm and 802 nm) is basically the same (about 15), and the adjustment period is 2.4 fs and 2.8 fs. The achievement of the near field control is attributed to the coherent superposition of SPP-excited LSP with light-excited LSP. In addition, the dephasing time of the coupling field was investigated using quasi- normal mode. It is found that the nanorod structure will correspond to different dephasing time under different relative time delay between two excitation light beams. Specifically, for the time delay of 0.72 fs (Δt=0.72 fs), the corresponding dephasing time for both modes is the same of 6.0 fs. For Δt=1.92 fs, the dephasing time of the longer-wavelength mode is 7.1 fs, and the one of the shorter-wavelength mode is 5.8 fs. We attribute the variation of the dephasing time to different coupling strength between the two modes at different delay times. This study may further promote the application of plasmons in the fields of surface-enhanced Raman scattering and plasmon assisted catalysis.
{"title":"Near-field control of gold nanostructure by the interaction of SPP and incident light","authors":"Wang Yue, Wang Lun, Sun Baixun, Lang Peng, Xu Yang, Zhao Zhenlong, Song Xiaowei, Ji Boyu, Lin Jingquan","doi":"10.7498/aps.72.20230514","DOIUrl":"https://doi.org/10.7498/aps.72.20230514","url":null,"abstract":"Localized Surface Plasmon (LSP) in nanostructure excited by Surface Plasmon Polariton (SPP) corresponds to stronger near-field enhancement and special spectral and dynamic responses that provides a new path to explore the interaction between light and matter. Meanwhile, this scheme can also release the signal background noise and structural thermal effect, and improve the performance of plasmonic components and sensing detectors based on LSP. However, the current research on this aspect is still insufficient. In this paper, we investigated the near-field characteristics of a plasmon composite structure composed of plasmon focusing lens and gold nanorod under the excitation of dual-beam using Finite-Difference Time-Domain (FDTD) method. The result shows that the near-field intensity control on the upper surface and in the gap position of the nanorod can be achieved by adjusting the relative time delay between the first light beam (used to excite SPP) and the second light beam (used to excite LSP). Specifically, the maximum adjustment range of the near-field intensity corresponding to 770 nm resonant mode in the gap position is about 23, and the adjustment period is about 2.4 fs. In a resonant mode dominated by SPP at a wavelength of 999 nm, the near-field intensity adjustment range is as small as 6, and the adjustment period is about 4 fs. On the upper surface of the structure, the adjustment range of the near-field intensity of the two resonant modes (719 nm and 802 nm) is basically the same (about 15), and the adjustment period is 2.4 fs and 2.8 fs. The achievement of the near field control is attributed to the coherent superposition of SPP-excited LSP with light-excited LSP. In addition, the dephasing time of the coupling field was investigated using quasi- normal mode. It is found that the nanorod structure will correspond to different dephasing time under different relative time delay between two excitation light beams. Specifically, for the time delay of 0.72 fs (Δt=0.72 fs), the corresponding dephasing time for both modes is the same of 6.0 fs. For Δt=1.92 fs, the dephasing time of the longer-wavelength mode is 7.1 fs, and the one of the shorter-wavelength mode is 5.8 fs. We attribute the variation of the dephasing time to different coupling strength between the two modes at different delay times. This study may further promote the application of plasmons in the fields of surface-enhanced Raman scattering and plasmon assisted catalysis.","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":"74771382","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}
Zeng Bai-yun, Gu Peng-yu, Jiang Shi-min, Jia Xin-Yan, Fan Dai-He
Quantum nonlocality is one of the most fundamental characteristics of quantum theory. As a commonly used quantum state generated in experiments, the "X" state is a typical one in the research of open quantum systems, since it still maintains the stability of the "X" shape during the evolution. Using the Clauser-Horne-Harmony-Holt (CHSH) inequality, the quantum nonlocality testing of two "X" states associated with local transformation operations is studied under the Markov environment. The results show that in the phase damping environment, the two "X" states have the same CHSH inequality testing results with the increasing of the evolution time. Moreover, the maximum of quantum nonlocality test of the two "X" states will decrease nonlinearly. When 0.78<F<1, the maximum value Sm of testing quantum nonlocality will gradually transition from Sm>2 to Sm<2 with the increasing of the evolution time of the two "X" states, and the research on the quantum nonlocality test cannot be successfully carried out. In the amplitude damping environment, using the "X" state obtained by the local transformation operation have a longer evolution time for the successfully quantum nonlocality testing when F>1. In particular, when F=1, the "X" state with the density matrix $rho _W$ cannot successfully perform the quantum nonlocality testing after the evolution time $Gamma t > 0.22$. For the "X" state with density matrix ${tilde rho _W}$, the quantum nonlocality testing cannot be performed until the evolution time $Gamma t > 0.26$. This results show that the local transformation operation of the "X" state is more conducive to the quantum nonlocality testing based on the CHSH inequality. Finally, the fidelity ranges of successfully testing the quantum nonlocality of the two "X" states in phase and amplitude damping environments are given in detail. The results show that, on the premise of quantum nonlocality testing successfully, the two types of "X" states evolving in the phase damping environment have the large range of valid fidelity. Meanwhile, at the same evolution time, the local transformation operation is helpful to improve the fidelity range of quantum nonlocality test in amplitude damping environment for "X" state with density matrix ${rho _W}$.
量子非定域性是量子理论最基本的特征之一。“X”态是实验中常用的一种量子态，在开放量子系统的研究中是一种典型的量子态，它在演化过程中仍然保持着“X”形的稳定性。利用clauser - horn - harmony - holt (CHSH)不等式，研究了马尔可夫环境下与局部变换操作相关的两个“X”态的量子非局域性检验。结果表明:在相位阻尼环境下，随着演化时间的增加，两种“X”态的CHSH不均匀性测试结果相同;此外，两个“X”态的量子非局域性检验的最大值将非线性地减小。当0.78F2比Sm1。特别是当F=1时，密度矩阵$rho _W$的“X”态在演化时间$Gamma t > 0.22$后无法成功进行量子非局域性测试。对于密度矩阵为${tilde rho _W}$的“X”态，要到演化时间$Gamma t > 0.26$才能进行量子非局域性测试。结果表明，“X”态的局部变换操作更有利于基于CHSH不等式的量子非局域性检验。最后，给出了在相位和振幅阻尼环境下成功测试两个“X”态量子非局域性的保真度范围。结果表明，在量子非局域性测试成功的前提下，在相位阻尼环境下演化的两类“X”态具有较大的有效保真度范围。同时，在相同的演化时间内，局部变换操作有助于提高具有密度矩阵${rho _W}$的“X”态在振幅阻尼环境下量子非局域测试的保真范围。
{"title":"Quantum nonlocality testing of the “X” state based on the CHSH inequality in Markov Environment","authors":"Zeng Bai-yun, Gu Peng-yu, Jiang Shi-min, Jia Xin-Yan, Fan Dai-He","doi":"10.7498/aps.72.20222218","DOIUrl":"https://doi.org/10.7498/aps.72.20222218","url":null,"abstract":"Quantum nonlocality is one of the most fundamental characteristics of quantum theory. As a commonly used quantum state generated in experiments, the \"X\" state is a typical one in the research of open quantum systems, since it still maintains the stability of the \"X\" shape during the evolution. Using the Clauser-Horne-Harmony-Holt (CHSH) inequality, the quantum nonlocality testing of two \"X\" states associated with local transformation operations is studied under the Markov environment. The results show that in the phase damping environment, the two \"X\" states have the same CHSH inequality testing results with the increasing of the evolution time. Moreover, the maximum of quantum nonlocality test of the two \"X\" states will decrease nonlinearly. When 0.78<<i>F<1, the maximum value Sm of testing quantum nonlocality will gradually transition from Sm>2 to Sm<2 with the increasing of the evolution time of the two \"X\" states, and the research on the quantum nonlocality test cannot be successfully carried out. In the amplitude damping environment, using the \"X\" state obtained by the local transformation operation have a longer evolution time for the successfully quantum nonlocality testing when F>1. In particular, when F=1, the \"X\" state with the density matrix $rho _W$ cannot successfully perform the quantum nonlocality testing after the evolution time $Gamma t > 0.22$. For the \"X\" state with density matrix ${tilde rho _W}$, the quantum nonlocality testing cannot be performed until the evolution time $Gamma t > 0.26$. This results show that the local transformation operation of the \"X\" state is more conducive to the quantum nonlocality testing based on the CHSH inequality. Finally, the fidelity ranges of successfully testing the quantum nonlocality of the two \"X\" states in phase and amplitude damping environments are given in detail. The results show that, on the premise of quantum nonlocality testing successfully, the two types of \"X\" states evolving in the phase damping environment have the large range of valid fidelity. Meanwhile, at the same evolution time, the local transformation operation is helpful to improve the fidelity range of quantum nonlocality test in amplitude damping environment for \"X\" state with density matrix ${rho _W}$.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"3 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78427664","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}
Topological pumping enables the quantized transport of matter waves through an adiabatic evolution of the system, which plays an essential role in the applications of transferring quantum states and exploring the topological properties in higher-dimensional quantum systems. Recently, exploring the interplay between novel topological pumping and interactions has attracted growing attention in topological systems, such as nonlinear topological pumping induced by interactions. So far, the experimental realizations of the nonlinear topological pumps have been realized only in the optical waveguide systems with Kerr nonlinearity. It is still necessary to further explore the phenomenon in different systems. Here, we present an experimental proposal for realizing the nonlinear topological pumping via a one-dimensional (1D) off-diagonal Aubry-André-Harper (AAH) model with mean-field interactions in the momentum space lattice of ultracold atoms. In particular, we develop a numerical method for calculating the energy band of the nonlinear systems. With numerical calculations, we first solve the nonlinear energy band structure and soliton solution of the 1D nonlinear off-diagonal AAH model in the region of weak interaction strengths. The result shows that the lowest or the highest energy band is modulated in the nonlinear system of g>0 or g<0, respectively. The eigenstates of the associated energy bands have the features of the soliton solutions. We then show that the topological pumping of solitons exhibits quantized transport characteristics. Moreover, we numerically calculate the Chern number associated with the lowest and highest energy bands at different interaction strengths. The result shows that the quantized transport of solitons is determined by the Chern number of the associated energy band of the system from which solitons emanate. Finally, we propose a nonlinear topological pumping scheme based on a momentum lattice experimental system with 7Li atoms. We can prepare the initial state, which is approximately the distribution of the soliton state of the lowest energy band, and calculate the dynamical evolution of this initial state in the case of U>0. Also, we analyzethe influence of adiabatic evolution conditions on the pumping process, demonstrating the feasibility of nonlinear topological pumping in the momentum lattice system. Our study provides a feasible route for investigating nonlinear topological pumping in ultracold atom systems, which is helpful for further exploring the topological transport in nonlinear systems, such as topological phase transitions and edge effects induced by nonlinearity.
{"title":"Nonlinear Topological Pumping in Momentum Space Lattice of Ultracold atoms","authors":"Yuan Tao, Dai Han-Ning, Chen Yu-Ao","doi":"10.7498/aps.72.20230740","DOIUrl":"https://doi.org/10.7498/aps.72.20230740","url":null,"abstract":"Topological pumping enables the quantized transport of matter waves through an adiabatic evolution of the system, which plays an essential role in the applications of transferring quantum states and exploring the topological properties in higher-dimensional quantum systems. Recently, exploring the interplay between novel topological pumping and interactions has attracted growing attention in topological systems, such as nonlinear topological pumping induced by interactions. So far, the experimental realizations of the nonlinear topological pumps have been realized only in the optical waveguide systems with Kerr nonlinearity. It is still necessary to further explore the phenomenon in different systems. Here, we present an experimental proposal for realizing the nonlinear topological pumping via a one-dimensional (1D) off-diagonal Aubry-André-Harper (AAH) model with mean-field interactions in the momentum space lattice of ultracold atoms. In particular, we develop a numerical method for calculating the energy band of the nonlinear systems. With numerical calculations, we first solve the nonlinear energy band structure and soliton solution of the 1D nonlinear off-diagonal AAH model in the region of weak interaction strengths. The result shows that the lowest or the highest energy band is modulated in the nonlinear system of g>0 or g<0, respectively. The eigenstates of the associated energy bands have the features of the soliton solutions. We then show that the topological pumping of solitons exhibits quantized transport characteristics. Moreover, we numerically calculate the Chern number associated with the lowest and highest energy bands at different interaction strengths. The result shows that the quantized transport of solitons is determined by the Chern number of the associated energy band of the system from which solitons emanate. Finally, we propose a nonlinear topological pumping scheme based on a momentum lattice experimental system with 7Li atoms. We can prepare the initial state, which is approximately the distribution of the soliton state of the lowest energy band, and calculate the dynamical evolution of this initial state in the case of U>0. Also, we analyzethe influence of adiabatic evolution conditions on the pumping process, demonstrating the feasibility of nonlinear topological pumping in the momentum lattice system. Our study provides a feasible route for investigating nonlinear topological pumping in ultracold atom systems, which is helpful for further exploring the topological transport in nonlinear systems, such as topological phase transitions and edge effects induced by nonlinearity.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"67 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79098122","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}
Zhu Cheng, Chen Xian-Hui, Wang Cheng, Song, Ming, Xia Wei-dong
In this paper, the composition, thermodynamic properties and transport coefficients of the argon-carbon-silicon plasma at local thermodynamic equilibrium(LTE) and local chemical equilibrium(LCE) for a wide range of temperatures (300 K – 30000 K) and pressures (0.1 atm - 10 atm) and different mixture ratios are presented. The condensed phases and Debye–Hückel corrections are both taken into account. The equilibrium component in gas phase is calculated by mass action law (Saha’s law and Gulberg–Waage’s law), Dalton's partial pressure law, conservation of the elements and charge quasi-neutral equation, while the condensed species is calculated by the local phase equilibrium assumption. Thermodynamic properties include density, enthalpy and specific heat are evaluated through a classical statistical mechanics approach. Transport coefficient calculations include viscosity, electrical conductivity, and thermal conductivity using a third-order approximation (second-order for viscosity) of the Chapman-Enskog method. Collision integrals are obtained using the relatively new data. The results show that the concentration and ratio of CSi vapor has a great influence on the properties of the Ar plasma by introducing not only the CSi vapor’ s own properties, but also new reactions. While the pressure influence those properties by the shift of chemical equilibrium and the changes of total number density. In addition, the introduction of condensed species makes the thermodynamic properties and transport coefficients of the lower temperature plasma are almost the same as those of pure argon, and causes discontinuous points at phase-transition temperature. The final calculation results are in good agreement with the literature comparison, and the difference is due to the different use of collision integral. The results are expected to provide reliable basic data for the numerical simulation of argon-carbon-silicon plasma.
本文研究了在较宽的温度范围(300 K ~ 30000 K)和压力范围(0.1 atm ~ 10 atm)及不同混合比下，氩-碳-硅等离子体在局部热力学平衡(LTE)和局部化学平衡(LCE)下的组成、热力学性质和输运系数。缩合相和德拜-赫克尔校正都被考虑在内。气相平衡组分采用质量作用定律(Saha定律和Gulberg-Waage定律)、道尔顿分压定律、元素守恒和电荷准中性方程计算，凝聚态组分采用局部相平衡假设计算。热力学性质包括密度，焓和比热通过经典的统计力学方法进行评估。输运系数的计算包括粘度、电导率和导热系数，使用Chapman-Enskog方法的三阶近似(粘度为二阶)。使用相对较新的数据获得碰撞积分。结果表明，CSi蒸气的浓度和比例对Ar等离子体的性质有很大的影响，不仅引入了CSi蒸气本身的性质，而且引入了新的反应。而压力则通过化学平衡的改变和总数目密度的变化来影响这些性质。此外，凝聚态的引入使得低温等离子体的热力学性质和输运系数与纯氩几乎相同，并且在相变温度处产生不连续点。最终计算结果与文献比较吻合较好，差异是由于碰撞积分的使用方法不同造成的。研究结果有望为氩碳硅等离子体的数值模拟提供可靠的基础数据。
{"title":"Calculation of thermodynamic properties and transport coefficients of Ar-C-Si Plasma","authors":"Zhu Cheng, Chen Xian-Hui, Wang Cheng, Song, Ming, Xia Wei-dong","doi":"10.7498/aps.72.20222390","DOIUrl":"https://doi.org/10.7498/aps.72.20222390","url":null,"abstract":"In this paper, the composition, thermodynamic properties and transport coefficients of the argon-carbon-silicon plasma at local thermodynamic equilibrium(LTE) and local chemical equilibrium(LCE) for a wide range of temperatures (300 K – 30000 K) and pressures (0.1 atm - 10 atm) and different mixture ratios are presented. The condensed phases and Debye–Hückel corrections are both taken into account. The equilibrium component in gas phase is calculated by mass action law (Saha’s law and Gulberg–Waage’s law), Dalton's partial pressure law, conservation of the elements and charge quasi-neutral equation, while the condensed species is calculated by the local phase equilibrium assumption. Thermodynamic properties include density, enthalpy and specific heat are evaluated through a classical statistical mechanics approach. Transport coefficient calculations include viscosity, electrical conductivity, and thermal conductivity using a third-order approximation (second-order for viscosity) of the Chapman-Enskog method. Collision integrals are obtained using the relatively new data. The results show that the concentration and ratio of CSi vapor has a great influence on the properties of the Ar plasma by introducing not only the CSi vapor’ s own properties, but also new reactions. While the pressure influence those properties by the shift of chemical equilibrium and the changes of total number density. In addition, the introduction of condensed species makes the thermodynamic properties and transport coefficients of the lower temperature plasma are almost the same as those of pure argon, and causes discontinuous points at phase-transition temperature. The final calculation results are in good agreement with the literature comparison, and the difference is due to the different use of collision integral. The results are expected to provide reliable basic data for the numerical simulation of argon-carbon-silicon plasma.","PeriodicalId":6995,"journal":{"name":"物理学报","volume":"48 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81610229","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：