Physics Letters A最新文献_第10页

Polyacene-based spintronic devices modulated by doping with two nitrogen or boron atoms and hydrogenation effects 用掺杂两个氮或硼原子和氢化效应调制聚二烯基自旋电子器件

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-06 DOI: 10.1016/j.physleta.2025.130628

Lihua Wang , Lexiang Zhao , Bingjun Ding

引用次数: 0

All-optical logical gates AND, OR, NOT, XNOR and XOR based on metalenses at 1.55 µm 基于1.55µm超透镜的全光逻辑门AND、OR、NOT、XOR和XOR

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-05 DOI: 10.1016/j.physleta.2025.130623

Hongbin Zhang , Lei Qin , Bin Wang , Shang Wang

{"title":"All-optical logical gates AND, OR, NOT, XNOR and XOR based on metalenses at 1.55 µm","authors":"Hongbin Zhang , Lei Qin , Bin Wang , Shang Wang","doi":"10.1016/j.physleta.2025.130623","DOIUrl":"10.1016/j.physleta.2025.130623","url":null,"abstract":"<div><div>This paper presents a novel approach for high-speed optical logic gates based on metalenses. The logic gates consist of two or three phase-controllable metalenses, which can apply different phases to multiple incident light beams of the same initial phase, converging them to a common focal point. This generates interference, enabling logical operations. The advantages of this work include the flexible phase control capabilities of the metalenses, which break the stringent input-phase requirements typically associated with optical logic devices. Additionally, since light predominantly propagates through air, this enhances information transmission rates. The miniaturization of metalenses also offers a potential pathway for achieving efficient parallel computing. The achievable types of logic gates include AND, OR, NOT, XNOR, and XOR, with theoretical contrast ratio of 39.51 dB (OR), 19.21 dB (AND), 11.45 dB (NOT), 11.54 dB (XNOR), and 14.61 dB (XOR). Due to the identical structure, the bit rate for each logic gate stabilizes between 1.04 and 1.05 Tb/s at a 50 % duty cycle. The excellent performance and rapid transmission speeds validate the feasibility of implementing optical logic gates using metalenses.</div></div>","PeriodicalId":20172,"journal":{"name":"Physics Letters A","volume":"551 ","pages":"Article 130623"},"PeriodicalIF":2.3,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143922428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Optimizing thermoelectric performance of halide perovskite Ca3AsBr3 through strain engineering 通过应变工程优化卤化钙钛矿Ca3AsBr3的热电性能

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-05 DOI: 10.1016/j.physleta.2025.130625

Sumedha Yadav, Sangeeta, Kulwinder Kumar, Mukhtiyar Singh

{"title":"Optimizing thermoelectric performance of halide perovskite Ca3AsBr3 through strain engineering","authors":"Sumedha Yadav, Sangeeta, Kulwinder Kumar, Mukhtiyar Singh","doi":"10.1016/j.physleta.2025.130625","DOIUrl":"10.1016/j.physleta.2025.130625","url":null,"abstract":"<div><div>We investigate structural, dynamical, elastic, electronic, and thermoelectric properties of cubic perovskite halide Ca<sub>3</sub>AsBr<sub>3</sub> under the effect of strain using first-principles calculations. It is found to have a direct bandgap of 2.425 eV that further reduces under compressive strain making it an ideal candidate for thermoelectric application. The material satisfies various stability criteria, e.g., dynamical, thermodynamical, and mechanical. The transport calculations show the highest Seebeck coefficient of value -458.227 μVK⁻¹ at 700 K for <em>n</em>-type Ca<sub>3</sub>AsBr<sub>3</sub> unstrained structure at carrier concentration 1 × 10<sup>21</sup> cm⁻³, which is further enhanced to -482.366 μVK⁻¹ for -2 % strain. The lattice thermal conductivity of the material is reduced from 1.243 Wm<sup>-1</sup>K<sup>-1</sup> to 0.627 Wm<sup>-1</sup>K<sup>-1</sup> at 700 K under 3 % strain. This low thermal conductivity, coupled with positive power factor values, results in increased peak thermoelectric figure of merit from 0.36 (unstrained) to 0.56 (+3 % strain) at 700 K for an <em>n</em>-type doping concentration of 1 × 10<sup>20</sup> cm⁻³.</div></div>","PeriodicalId":20172,"journal":{"name":"Physics Letters A","volume":"551 ","pages":"Article 130625"},"PeriodicalIF":2.3,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Invariants of flows in 4-d space time 四维时空中流动的不变量

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-05 DOI: 10.1016/j.physleta.2025.130602

Susan Mathew Panakkal , Parameswaran R. , Vedan M.J.

引用次数: 0

Analysis of plankton-fish system with delay of fear effect 具有延迟恐惧效应的浮游生物-鱼类系统分析

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-05 DOI: 10.1016/j.physleta.2025.130583

Renxiang Shi

{"title":"Analysis of plankton-fish system with delay of fear effect","authors":"Renxiang Shi","doi":"10.1016/j.physleta.2025.130583","DOIUrl":"10.1016/j.physleta.2025.130583","url":null,"abstract":"<div><div>We propose a three dimensional system including phytoplankton, zooplankton and fish, which describes the food chain between plankton and fish. We take Holling-II functional response to describe the predation ability of fish and zooplankton. For fear effect of predator exists in reality, so we introduce fear effect of fish into system, besides we think the influence of fear effect is not instantaneous, delay of fear effect has been included. We study the dynamics of plankton-fish system with delay of fear effect. First we study the positivity and boundedness of solution, which mean that all the species exist and their increase is limited by environment, then taking the delay of fear effect as parameter, we discuss Hopf bifurcation, estimate the length of delay to preserve the stability of limit cycle. At last, we give simulations about the influence of delay of fear effect on the dynamics of plankton-fish system and the sensitivity analysis of parameters on the density of plankton and fish without delay. Our results show that delay of fear effect can cause periodic oscillation and chaos for plankton-fish system, uptake rate of fish to zooplankton and death rate of fish have large impact on the density of plankton and fish.</div></div>","PeriodicalId":20172,"journal":{"name":"Physics Letters A","volume":"551 ","pages":"Article 130583"},"PeriodicalIF":2.3,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Optical torques in the folding Fabry–Perot cavity 折叠法布里-珀罗腔中的光力矩

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-04 DOI: 10.1016/j.physleta.2025.130600

Xingrui Peng , Denis Martynov , Zonghong Zhu , Teng Zhang

{"title":"Optical torques in the folding Fabry–Perot cavity","authors":"Xingrui Peng , Denis Martynov , Zonghong Zhu , Teng Zhang","doi":"10.1016/j.physleta.2025.130600","DOIUrl":"10.1016/j.physleta.2025.130600","url":null,"abstract":"<div><div>Folding the Fabry-Perot cavity allows gravitational wave detectors to enhance their effective arm lengths. However, a different number of mirrors and geometry of the folded cavity will complicate the dynamics of the mirrors under the exertion of radiation pressure forces and torques. This paper gives the framework for analysing the stability of folded cavities in the angular degrees of freedom. In particular, we analyse the optical torques and mirror dynamics of the trifold 12 km cavity, which can serve as a potential upgrade of aLIGO for the kilo-Hertz sensitivity boosting. We explore feasible geometric configurations supporting the target arm cavity power of 1.5 MW and the resulting coating thermal noise. Our analysis suggests that the cavity remains stable by replicating the current arm cavity geometry three times and increasing all mirror masses to 200 kg. It gives thermal noise, <span><math><mn>2.94</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>24</mn></mrow></msup><mspace></mspace><mo>/</mo><mspace></mspace><msqrt><mrow><mtext>Hz</mtext></mrow></msqrt></math></span> at 100 Hz, 8.5% higher than the aLIGO design.</div></div>","PeriodicalId":20172,"journal":{"name":"Physics Letters A","volume":"550 ","pages":"Article 130600"},"PeriodicalIF":2.3,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143903270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Comment on “Symmetric twin paradox for free-falling frames: Argument against the relativistic time dilation?” 评论“自由落体坐标系的对称孪生悖论：反对相对论性时间膨胀的论证？”

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-02 DOI: 10.1016/j.physleta.2025.130579

Justo Pastor Lambare

引用次数: 0

Electric current quantum superpositions in superconducting circuits 超导电路中的电流量子叠加

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-02 DOI: 10.1016/j.physleta.2025.130599

Caio C. Holanda Ribeiro , Vitoria A. de Souza , Vitorio A. De Lorenci

引用次数: 0

Quantum information recast via multiresolution in L2(0,1] 基于L2（0,1）的多分辨率量子信息重构

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-02 DOI: 10.1016/j.physleta.2025.130601

Mandana Bidarvand, Artur Sowa

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CaB11−: A unique four-ring conjugated dual aromatic system CaB11−：一种独特的四环共轭双芳香体系

IF 2.3 3区物理与天体物理

Physics Letters A Pub Date : 2025-05-01 DOI: 10.1016/j.physleta.2025.130585

Qian Wang , Yan Fei Hu , De Hui Zhou , Zhi Wei Tan , Yu Tong Liu , Tian Yi Zhang , Yu Quan Yuan

{"title":"CaB11−: A unique four-ring conjugated dual aromatic system","authors":"Qian Wang , Yan Fei Hu , De Hui Zhou , Zhi Wei Tan , Yu Tong Liu , Tian Yi Zhang , Yu Quan Yuan","doi":"10.1016/j.physleta.2025.130585","DOIUrl":"10.1016/j.physleta.2025.130585","url":null,"abstract":"<div><div>At the B3LYP/6–311G(d) level, we obtained the ground state structures of CaB<sub>n</sub><sup>0/−</sup> (<em>n</em> = 2–12). Observing the evolution characteristics of these structures, we found that the transition from two-dimensional to three-dimensional structures occurs when the number of boron atoms equals 6 (for the neutral system) and 7 (for the anionic system). For the three-dimensional structure, the Ca atom is always positioned above the plane or quasi-plane formed by the boron atoms (at the vertex position), similar to an umbrella-like structure. In most cases, the neutral and anionic structures with the same number of boron atoms are consistent. The only exceptions are CaB<sub>6</sub><sup>−</sup> and CaB<sub>11</sub><sup>−</sup>, where the neutral structure is three-dimensional, but upon adding an electron, they transform into a two-dimensional planar structure. This peculiarity persists in the stability analysis, and according to the results, the CaB<sub>11</sub><sup>−</sup> structure with C<sub>2V</sub> symmetry is the most stable. A detailed analysis of the bonding situation in CaB<sub>11</sub><sup>−</sup> reveals that it is a planar structure with four conjugated rings, where adjacent atoms in each ring are connected by covalent bonds, B-B bonds are in the form of covalent single bonds, and Ca-B bonds are in the form of covalent half-bonds. The charge on the Ca atom unexpectedly transfers to the neighboring boron atoms; however, the valence electrons on Ca do not completely transfer, resulting in <em>a</em> + 2 charge, but rather retain some valence electrons, which interact with the valence electrons of the adjacent boron atoms to form half-bonds. The main interaction between Ca and B is still ionic bonding. All four rings are aromatic, with the central ring having the strongest aromaticity. The entire CaB<sub>11</sub><sup>−</sup> exhibits dual aromaticity of σ/π types.</div></div>","PeriodicalId":20172,"journal":{"name":"Physics Letters A","volume":"550 ","pages":"Article 130585"},"PeriodicalIF":2.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143917778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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