Pub Date : 2024-01-12DOI: 10.1134/s106377612311002x
M. Yu. Azarkin, M. R. Kirakosyan
Abstract
This paper presents an overview of Monte Carlo (MC) event generators for simulation of proton-proton collisions along with the results on hadron production at nuclotron-based ion collider facility (NICA) energies. Namely, mean multiplicities, mean transverse momenta, and rapidity distributions of p((bar {p})), π±, K± at different collision energies are presented. We also study two-particle angular correlations for stable charged particles. Results of simulations with PYTHIA, EPOS, SMASH, and UrQMD event generators are compared to available data. Connections of studied quantities with physics mechanisms in MC generators are discussed. We suggest a tuned set of parameters to address observed discrepancies between data and PYTHIA.
摘要 本文概述了用于模拟质子-质子对撞的蒙特卡罗(MC)事件发生器,以及基于核素的离子对撞机设施(NICA)能量下强子产生的结果。即,介绍了不同对撞能量下p((bar {p}))、π±、K±的平均倍率、平均横截面矩和快速性分布。我们还研究了稳定带电粒子的双粒子角相关性。使用PYTHIA、EPOS、SMASH和UrQMD事件发生器模拟的结果与现有数据进行了比较。讨论了所研究的量与 MC 发生器中物理机制的联系。我们建议调整一组参数,以解决观察到的数据与PYTHIA之间的差异。
{"title":"Performance of Monte Carlo Event Generators of pp Collisions at NICA Energies","authors":"M. Yu. Azarkin, M. R. Kirakosyan","doi":"10.1134/s106377612311002x","DOIUrl":"https://doi.org/10.1134/s106377612311002x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>This paper presents an overview of Monte Carlo (MC) event generators for simulation of proton-proton collisions along with the results on hadron production at nuclotron-based ion collider facility (NICA) energies. Namely, mean multiplicities, mean transverse momenta, and rapidity distributions of <i>p</i>(<span>(bar {p})</span>), π<sup>±</sup>, <i>K</i><sup>±</sup> at different collision energies are presented. We also study two-particle angular correlations for stable charged particles. Results of simulations with PYTHIA, EPOS, SMASH, and UrQMD event generators are compared to available data. Connections of studied quantities with physics mechanisms in MC generators are discussed. We suggest a tuned set of parameters to address observed discrepancies between data and PYTHIA.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462258","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110109
N. I. Solin, S. V. Naumov, A. V. Korolev, V. R. Galakhov
Abstract
The spin states of Co atoms in PrBaCo2O5 + δ with regard to the paramagnetic contribution of Pr3+ ions have been determined from magnetic property studies for δ = 0.52 and 0.74. Results obtained without considering the paramagnetic contribution of Pr3+ ions are inconsistent with available experimental data. With a decrease in temperature, the metal–insulator transition in PrBaCo2O5.52 becomes sharper according to a sharp change in spin states (from HS/LS to LS/IS) of Co3+ ions. In this case, Co3+ ions occupying octahedra pass from the high-spin state (HS, S = 2) to the low-spin one (LS, S = 0) and those occupying pyramids pass from the LS-state to the intermediate spin state (IS, S = 1), as follows from the available structural data. In PrBaCo2O5.74, the metal–semiconductor transition occurs smoothly from HS/LS to the HS/IS state upon the smooth transition of the Co3+ ion state from (LS, S = 0) to the (IS, S = 1) state in pyramides without change in the spin state of ions Co3+ (HS, S = 2) and Co4+ (LS, S = 1/2) in octahedrons.
{"title":"Spin States of Cobalt Ions and a Metal–Semiconductor Transition in Layered Cobaltites PrBaCo2O5 + δ (δ = 0.52, 0.74)","authors":"N. I. Solin, S. V. Naumov, A. V. Korolev, V. R. Galakhov","doi":"10.1134/s1063776123110109","DOIUrl":"https://doi.org/10.1134/s1063776123110109","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The spin states of Co atoms in PrBaCo<sub>2</sub>O<sub>5 + δ</sub> with regard to the paramagnetic contribution of Pr<sup>3+</sup> ions have been determined from magnetic property studies for δ = 0.52 and 0.74. Results obtained without considering the paramagnetic contribution of Pr<sup>3+</sup> ions are inconsistent with available experimental data. With a decrease in temperature, the metal–insulator transition in PrBaCo<sub>2</sub>O<sub>5.52</sub> becomes sharper according to a sharp change in spin states (from HS/LS to LS/IS) of Co<sup>3+</sup> ions. In this case, Co<sup>3+</sup> ions occupying octahedra pass from the high-spin state (HS, <i>S</i> = 2) to the low-spin one (LS, <i>S</i> = 0) and those occupying pyramids pass from the LS-state to the intermediate spin state (IS, <i>S</i> = 1), as follows from the available structural data. In PrBaCo<sub>2</sub>O<sub>5.74</sub>, the metal–semiconductor transition occurs smoothly from HS/LS to the HS/IS state upon the smooth transition of the Co<sup>3+</sup> ion state from (LS, <i>S</i> = 0) to the (IS, <i>S</i> = 1) state in pyramides without change in the spin state of ions Co<sup>3+</sup> (HS, <i>S</i> = 2) and Co<sup>4+</sup> (LS, <i>S</i> = 1/2) in octahedrons.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462575","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110043
A. M. Kamchatnov
Abstract
A theory of conversion of an intense initial wave pulse into solitons for asymptotically long evolution times has been developed using the approach based on the fact that such a transformation occurs via an intermediate stage of formation and evolution of dispersion shock waves. The number of nonlinear oscillations in such waves turns out to be equal to the number of solitons in the asymptotic state. Using the Poincaré–Cartan integral invariant theory, it is shown that the number of oscillations equal to the classical action of a particle associated with the wave packet in the vicinity of the small-amplitude edge of a dispersion shock wave remains unchanged upon a transfer by a flow described by a nondispersive limit of the nonlinear wave equations considered here. This makes it possible to formulate a generalized Bohr–Sommerfeld quantization rule that determines the set of “eigenvalues” associated with soliton physical parameters in the asymptotic state (in particular, with their velocities). In the theory, the properties of full integrability of nonlinear wave equations are not used, but the corresponding results are reproduced in this case also. The analytical results are confirmed by numerical solutions to nonlinear wave equations.
{"title":"Asymptotic Theory of Solitons Generated from an Intense Wave Pulse","authors":"A. M. Kamchatnov","doi":"10.1134/s1063776123110043","DOIUrl":"https://doi.org/10.1134/s1063776123110043","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A theory of conversion of an intense initial wave pulse into solitons for asymptotically long evolution times has been developed using the approach based on the fact that such a transformation occurs via an intermediate stage of formation and evolution of dispersion shock waves. The number of nonlinear oscillations in such waves turns out to be equal to the number of solitons in the asymptotic state. Using the Poincaré–Cartan integral invariant theory, it is shown that the number of oscillations equal to the classical action of a particle associated with the wave packet in the vicinity of the small-amplitude edge of a dispersion shock wave remains unchanged upon a transfer by a flow described by a nondispersive limit of the nonlinear wave equations considered here. This makes it possible to formulate a generalized Bohr–Sommerfeld quantization rule that determines the set of “eigenvalues” associated with soliton physical parameters in the asymptotic state (in particular, with their velocities). In the theory, the properties of full integrability of nonlinear wave equations are not used, but the corresponding results are reproduced in this case also. The analytical results are confirmed by numerical solutions to nonlinear wave equations.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462257","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110055
V. E. Lobanov
Abstract
Pumping a high-Q optical microresonator by an external laser is inevitably associated with thermal effects. They have a significant impact on the dynamics of nonlinear processes in such structures, including the generation of optical frequency combs and dissipative solitons. The generation process and the properties of bright solitons in such heated microresonators with anomalous group velocity dispersion (GVD) have been well studied, and a number of methods have been developed to minimize the effect of thermal processes. However, for dark solitons or platicons excited at normal GVD, these issues have been studied significantly less. In this work, the properties of platicons in heated microresonators are analyzed, and it is shown that in the case of “positive” thermal effects, when the direction of the thermal shift of the resonance frequencies of a microresonator coincides with the direction of the nonlinear shift, the widest high-energy platicons with the duration close to the round trip time in the resonator are stable. In the case of “negative” thermal effects, narrow low-energy platicons remain stable. Moreover, in microresonators with “negative” thermal effects, the interaction between cubic nonlinear and thermal processes can ensure the generation of platicons without special techniques required in other cases.
{"title":"Effect of Heating on the Generation and Properties of Platicons in High-Q Optical Microresonators","authors":"V. E. Lobanov","doi":"10.1134/s1063776123110055","DOIUrl":"https://doi.org/10.1134/s1063776123110055","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Pumping a high-<i>Q</i> optical microresonator by an external laser is inevitably associated with thermal effects. They have a significant impact on the dynamics of nonlinear processes in such structures, including the generation of optical frequency combs and dissipative solitons. The generation process and the properties of bright solitons in such heated microresonators with anomalous group velocity dispersion (GVD) have been well studied, and a number of methods have been developed to minimize the effect of thermal processes. However, for dark solitons or platicons excited at normal GVD, these issues have been studied significantly less. In this work, the properties of platicons in heated microresonators are analyzed, and it is shown that in the case of “positive” thermal effects, when the direction of the thermal shift of the resonance frequencies of a microresonator coincides with the direction of the nonlinear shift, the widest high-energy platicons with the duration close to the round trip time in the resonator are stable. In the case of “negative” thermal effects, narrow low-energy platicons remain stable. Moreover, in microresonators with “negative” thermal effects, the interaction between cubic nonlinear and thermal processes can ensure the generation of platicons without special techniques required in other cases.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462259","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110031
O. N. Gorshkov, D. O. Filatov, M. N. Koriazhkina, V. A. Lobanova, M. A. Riabova
Abstract
The effect of Gaussian noise on the switching of a ZrO2(Y) based memristor from the low resistance state (LRS) into the high resistance state (HRS) including transitions from the LRS into intermediate metastable states has been studied. The series of positive (with addition of the noise signal or without the one) and negative rectangular voltage pulses were used as the switching signals. The adding of noise to the switching signal initiated the switching of the memristor from the LRS into the HRS at smaller pulse magnitudes than in the case of switching by the rectangular pulses without adding the noise. A necessary (preset) HRS can be achieved passing the intermediate states by adding the noise with certain parameters to the rectangular switching pulses. The resistive switching is performed without application of adaptive switching protocols. The results of the present study can be applied in the development of innovative memristor switching protocols.
{"title":"Effect of Noise on Resistive Switching of an Yttria Stabilized Zirconia Based Memristor","authors":"O. N. Gorshkov, D. O. Filatov, M. N. Koriazhkina, V. A. Lobanova, M. A. Riabova","doi":"10.1134/s1063776123110031","DOIUrl":"https://doi.org/10.1134/s1063776123110031","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The effect of Gaussian noise on the switching of a ZrO<sub>2</sub>(Y) based memristor from the low resistance state (LRS) into the high resistance state (HRS) including transitions from the LRS into intermediate metastable states has been studied. The series of positive (with addition of the noise signal or without the one) and negative rectangular voltage pulses were used as the switching signals. The adding of noise to the switching signal initiated the switching of the memristor from the LRS into the HRS at smaller pulse magnitudes than in the case of switching by the rectangular pulses without adding the noise. A necessary (preset) HRS can be achieved passing the intermediate states by adding the noise with certain parameters to the rectangular switching pulses. The resistive switching is performed without application of adaptive switching protocols. The results of the present study can be applied in the development of innovative memristor switching protocols.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462201","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110080
A. K. Murtazaev, M. K. Badiev, M. A. Magomedov, M. K. Ramazanov
Abstract
The phase transitions and thermodynamic properties of the clock model with q = 5 spin states on a triangular lattice have been investigated using the Wang–Landau Monte Carlo algorithm. The phase transitions have been analyzed with the histogram method and the fourth-order Binder cumulant method. Two Berezinskii–Kosterlitz–Thouless phase transitions are shown to be observed in the ferromagnetic clock model, while a second-order phase transition has been detected in the antiferromagnetic clock model.
{"title":"Phase Transitions in the Clock Model with q = 5 Spin States on a Triangular Lattice","authors":"A. K. Murtazaev, M. K. Badiev, M. A. Magomedov, M. K. Ramazanov","doi":"10.1134/s1063776123110080","DOIUrl":"https://doi.org/10.1134/s1063776123110080","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The phase transitions and thermodynamic properties of the clock model with <i>q</i> = 5 spin states on a triangular lattice have been investigated using the Wang–Landau Monte Carlo algorithm. The phase transitions have been analyzed with the histogram method and the fourth-order Binder cumulant method. Two Berezinskii–Kosterlitz–Thouless phase transitions are shown to be observed in the ferromagnetic clock model, while a second-order phase transition has been detected in the antiferromagnetic clock model.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462230","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}
{"title":"Erratum to: Vortex Dynamics in Superconducting MoN Strip with a Side Cut","authors":"S. S. Ustavschikov, M. Yu. Levichev, I. Yu. Pashen’kin, N. S. Gusev, S. A. Gusev, D. Yu. Vodolazov","doi":"10.1134/s1063776123110171","DOIUrl":"https://doi.org/10.1134/s1063776123110171","url":null,"abstract":"<p>An Erratum to this paper has been published: https://doi.org/10.1134/S1063776123110171</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462226","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110018
N. V. Agrinskaya, V. I. Kozub
Abstract
In a previous report, we presented experiments which suggested that ferromagnetic ordering of the spins of localized holes in GaAs/AlGaAs quantum wells could be observed when doped with shallow (Be) acceptors at impurity concentrations near the metal-insulator transition. The compensating impurity (Si) was introduced into a narrow region at the center of the barriers [4]. In this paper, we present results from magnetotransport experiments performed on similar structures, but without the compensating impurity (Si). In these samples, the compensation degree is expected to be controlled by the background defects located at the edges of the quantum wells and within the barriers. At low temperatures T ≤ 10 K, we observed isotropic, linear magnetoresistance, anomalous behavior of the Hall effect as a function of the magnetic field, and slow relaxation of resistance after the application of a magnetic field. We explain this anomalous magnetotransport as the manifestation of a ferromagnetic transition or spin glass, originating from indirect spin exchange between localized holes on impurities near the metal-insulator transition. However, we note that perfect disorder, including signs of interspin interactions, leads to unstable configurations. In what follows, we present a model in which we start with this perfect disorder, but apply a procedure to obtain a stable configuration. We show that the resulting spin structure, a “closely packed” structure of “droplets,” can reproduce the features observed in the experiment, particularly isotropic, linear magnetoresistance.
摘要 在之前的报告中,我们通过实验表明,在 GaAs/AlGaAs 量子阱中掺入浅(Be)受体,杂质浓度接近金属-绝缘体转变时,可以观察到局部空穴自旋的铁磁有序化。补偿杂质(硅)被引入到势垒中心的狭窄区域 [4]。在本文中,我们介绍了在类似结构上进行的磁传输实验结果,但没有补偿杂质(硅)。在这些样品中,补偿程度预计由量子阱边缘和势垒内的背景缺陷控制。在温度 T ≤ 10 K 的低温条件下,我们观察到了各向同性的线性磁阻、霍尔效应作为磁场函数的反常行为,以及施加磁场后电阻的缓慢弛豫。我们将这种反常的磁传输解释为铁磁转变或自旋玻璃的表现,它源于金属-绝缘体转变附近杂质上局部空穴之间的间接自旋交换。然而,我们注意到,完全无序(包括自旋间相互作用的迹象)会导致不稳定的构型。在下文中,我们将介绍一个模型,在这个模型中,我们从这种完全无序开始,但采用一种程序来获得稳定构型。我们展示了由此产生的自旋结构--"紧密堆积 "的 "液滴 "结构--能够再现实验中观察到的特征,尤其是各向同性的线性磁阻。
{"title":"Spin Glass Model for GaAs/AlGaAs Quantum Wells Doped by Nonmagnetic Impurities near the Metal-Insulator Transition","authors":"N. V. Agrinskaya, V. I. Kozub","doi":"10.1134/s1063776123110018","DOIUrl":"https://doi.org/10.1134/s1063776123110018","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In a previous report, we presented experiments which suggested that ferromagnetic ordering of the spins of localized holes in GaAs/AlGaAs quantum wells could be observed when doped with shallow (Be) acceptors at impurity concentrations near the metal-insulator transition. The compensating impurity (Si) was introduced into a narrow region at the center of the barriers [4]. In this paper, we present results from magnetotransport experiments performed on similar structures, but without the compensating impurity (Si). In these samples, the compensation degree is expected to be controlled by the background defects located at the edges of the quantum wells and within the barriers. At low temperatures <i>T</i> ≤ 10 K, we observed isotropic, linear magnetoresistance, anomalous behavior of the Hall effect as a function of the magnetic field, and slow relaxation of resistance after the application of a magnetic field. We explain this anomalous magnetotransport as the manifestation of a ferromagnetic transition or spin glass, originating from indirect spin exchange between localized holes on impurities near the metal-insulator transition. However, we note that perfect disorder, including signs of interspin interactions, leads to unstable configurations. In what follows, we present a model in which we start with this perfect disorder, but apply a procedure to obtain a stable configuration. We show that the resulting spin structure, a “closely packed” structure of “droplets,” can reproduce the features observed in the experiment, particularly isotropic, linear magnetoresistance.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462225","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110122
D. P. Agapov, I. V. Belovolov, S. A. Magnitskii, D. N. Frolovtsev, A. S. Chirkin
Abstract
The possibility of obtaining an object image using a fiber-optic endoscope based on ghost imaging principle is demonstrated experimentally. The endoscope consists of a multimode fiber and includes a radiation source with thermal statistics, which is formed by means of random modulation of He–Ne laser radiation with the help of a phase spatial light modulator. It is shown that after the passage through the fiber, the field preserves the pseudo-thermal statistics. Radiation obtained in this way is used for ghost imaging in transmitted as well as scattered light.
{"title":"Ghost Imaging in a Fiber-Optic Endoscope Based on Light Scattering","authors":"D. P. Agapov, I. V. Belovolov, S. A. Magnitskii, D. N. Frolovtsev, A. S. Chirkin","doi":"10.1134/s1063776123110122","DOIUrl":"https://doi.org/10.1134/s1063776123110122","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The possibility of obtaining an object image using a fiber-optic endoscope based on ghost imaging principle is demonstrated experimentally. The endoscope consists of a multimode fiber and includes a radiation source with thermal statistics, which is formed by means of random modulation of He–Ne laser radiation with the help of a phase spatial light modulator. It is shown that after the passage through the fiber, the field preserves the pseudo-thermal statistics. Radiation obtained in this way is used for ghost imaging in transmitted as well as scattered light.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139462229","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}
Pub Date : 2024-01-12DOI: 10.1134/s1063776123110079
A. Ya. Maltsev
Abstract
We consider the Lifshitz topological transitions and the corresponding changes in the galvano-magnetic properties of a metal from the point of view of the general classification of open electron trajectories arising on Fermi surfaces of arbitrary complexity in the presence of magnetic field. The construction of such a classification is the content of the Novikov problem and is based on the division of non-closed electron trajectories into topologically regular and chaotic trajectories. The description of stable topologically regular trajectories gives a basis for a complete classification of non-closed trajectories on arbitrary Fermi surfaces and is connected with special topological structures on these surfaces. Using this description, we describe here the distinctive features of possible changes in the picture of electron trajectories during the Lifshitz transitions, as well as changes in the conductivity behavior in the presence of a strong magnetic field. As it turns out, the use of such an approach makes it possible to describe not only the changes associated with stable electron trajectories, but also the most general changes of the conductivity diagram in strong magnetic fields.
{"title":"Lifshitz Transitions and Angular Conductivity Diagrams in Metals with Complex Fermi Surfaces","authors":"A. Ya. Maltsev","doi":"10.1134/s1063776123110079","DOIUrl":"https://doi.org/10.1134/s1063776123110079","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We consider the Lifshitz topological transitions and the corresponding changes in the galvano-magnetic properties of a metal from the point of view of the general classification of open electron trajectories arising on Fermi surfaces of arbitrary complexity in the presence of magnetic field. The construction of such a classification is the content of the Novikov problem and is based on the division of non-closed electron trajectories into topologically regular and chaotic trajectories. The description of stable topologically regular trajectories gives a basis for a complete classification of non-closed trajectories on arbitrary Fermi surfaces and is connected with special topological structures on these surfaces. Using this description, we describe here the distinctive features of possible changes in the picture of electron trajectories during the Lifshitz transitions, as well as changes in the conductivity behavior in the presence of a strong magnetic field. As it turns out, the use of such an approach makes it possible to describe not only the changes associated with stable electron trajectories, but also the most general changes of the conductivity diagram in strong magnetic fields.</p>","PeriodicalId":629,"journal":{"name":"Journal of Experimental and Theoretical Physics","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139465276","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}