New Journal of Physics最新文献_第6页

Large tunneling magnetoresistance and its high bias stability in Weyl half-semimetal based lateral magnetic tunnel junctions 基于韦尔半半亚金属的横向磁隧道结中的大隧道磁阻及其高偏置稳定性

New Journal of Physics Pub Date : 2024-03-15 DOI: 10.1088/1367-2630/ad345b

Jianing Tan, G. W. (. W. Yang, G. Ouyang

{"title":"Large tunneling magnetoresistance and its high bias stability in Weyl half-semimetal based lateral magnetic tunnel junctions","authors":"Jianing Tan, G. W. (. W. Yang, G. Ouyang","doi":"10.1088/1367-2630/ad345b","DOIUrl":"https://doi.org/10.1088/1367-2630/ad345b","url":null,"abstract":"\u0000 Magnetic tunnel junctions (MTJs) based on novel states of two-dimensional (2D) magnetic materials will significantly improve the value of the tunneling magnetoresistance (TMR) ratio. However, most 2D magnetic materials exhibit low critical temperatures, limiting their functionality to lower temperatures rather than room temperature. Moreover, most MTJs experience the decay of TMR ratio at large bias voltages within a low spin injection efficiency (SIE). Here, we construct a series of MTJs with Weyl half-semimetal (WHSM, e.g., MnSiS3, MnSiSe3, and MnGeSe3 monolayers) as the electrodes and investigate the spin-dependent transport properties in these kind of lateral heterojunctions by employing density functional theory combined with non-equilibrium Green’s function method. We find that an ultrahigh TMR (~109%) can be obtained firmly at a small bias voltage and maintains a high SIE even at a large bias voltage, and MnSiSe3 monolayer is predicted to exhibit a high critical temperature. Additionally, we reveal that the same structure allows for the generation of fully spin-polarized photocurrent, irrespective of the polarization angle. These findings underscore the potential of Weyl half-semimetals as candidate materials for high-performance spintronic devices.","PeriodicalId":508829,"journal":{"name":"New Journal of Physics","volume":"5 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140238997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anomalies-Rich Floquet Superconductivities Induced by Joint Modulation of Dynamic Driving and Static Parameters 动态驱动和静态参数联合调制诱导的富异常浮凸超导电性

New Journal of Physics Pub Date : 2024-03-14 DOI: 10.1088/1367-2630/ad33cf

Donghao Wang, Cong Cen, Liangliang Lu, Mengyao 李梦瑶, Zixuan Ding, Yongchun Tao, Jingguo Hu

{"title":"Anomalies-Rich Floquet Superconductivities Induced by Joint Modulation of Dynamic Driving and Static Parameters","authors":"Donghao Wang, Cong Cen, Liangliang Lu, Mengyao 李梦瑶, Zixuan Ding, Yongchun Tao, Jingguo Hu","doi":"10.1088/1367-2630/ad33cf","DOIUrl":"https://doi.org/10.1088/1367-2630/ad33cf","url":null,"abstract":"\u0000 Current theoretical and experimental endeavors to realize an anomalous Floquet chiral topological superconductor (TSC), which is characterized by chiral Majorana edge modes independent of the Chern number, remain insufficient. Herein, we propose a new scheme that involves jointly tuning dynamic driving and static parameters within a magnetic topological insulator-superconductor sandwich structure to achieve this goal. The Josephson phase modulation induced by an applied bias voltage across the structure is utilized as a Floquet periodic drive. It is found that the interplay between the two kinds of tunings can bring about a lot more exotic Floquet TSC phases than those caused by only tuning the dynamic driving parameter (frequency ω or period τ). More importantly, just tuning static parameters (the chemical potential µ, Zeeman field gz, and proximity-induced superconducting energy gap ∆b) also can induce a series of novel topological phase transitions. Particularly, the features in the context of the three tunings are different from each other, originating from the combination of intrinsic and different extrinsic mechanisms. In addition, jointly tuning τ and µ (gz) can have its own unique TSC phases. The proposed scheme should be readily accessible in experiments, and thus the family of anomalous Floquet TSC phases may be considerably enriched.","PeriodicalId":508829,"journal":{"name":"New Journal of Physics","volume":"20 S2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140243321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extended exceptional points in projected non-Hermitian systems 投影非ermitian 系统中的扩展例外点

New Journal of Physics Pub Date : 2024-03-11 DOI: 10.1088/1367-2630/ad327d

Xiao-Ran Wang, Fei Yang, Xian-Qi Tong, Xiao-Jie Yu, Kui Cao, S. Kou

引用次数: 0

Nonlocal correlations in quantum networks distributed with diﬀerent entangled states 分布着不同纠缠态的量子网络中的非局部相关性

New Journal of Physics Pub Date : 2024-03-07 DOI: 10.1088/1367-2630/ad313c

Li-Yi Hsu

引用次数: 0

Controllable Floquet topological phases in the magnetic ladder system 磁梯系统中的可控 Floquet 拓扑相位

New Journal of Physics Pub Date : 2024-03-06 DOI: 10.1088/1367-2630/ad309a

Xu-Jin Wang, Lu Zhang, Liang Yan, Jie-Yun Yan

引用次数: 0

A noise-robust quantum dynamics learning protocol based on Choi-Jamiolkowski Isomorphism: theory and experiment 基于 Choi-Jamiolkowski Isomorphism 的稳健噪声量子动力学学习协议：理论与实验

New Journal of Physics Pub Date : 2024-03-06 DOI: 10.1088/1367-2630/ad309d

Xin-Yu Chen, Pan Gao, Chu-Dan Qiu, Ya-Nan Lu, Fan Yang, Yuanyuan Zhao, Hang Li, Jiang Zhang, Shijie Wei, Tonghao Xing, Xin-Yu Pan, Dong Ruan, Feihao Zhang, Keren Li, Guilu Long

{"title":"A noise-robust quantum dynamics learning protocol based on Choi-Jamiolkowski Isomorphism: theory and experiment","authors":"Xin-Yu Chen, Pan Gao, Chu-Dan Qiu, Ya-Nan Lu, Fan Yang, Yuanyuan Zhao, Hang Li, Jiang Zhang, Shijie Wei, Tonghao Xing, Xin-Yu Pan, Dong Ruan, Feihao Zhang, Keren Li, Guilu Long","doi":"10.1088/1367-2630/ad309d","DOIUrl":"https://doi.org/10.1088/1367-2630/ad309d","url":null,"abstract":"\u0000 With the rapid development of quantum technology, the growing manipulated Hilbert space makes learning the dynamics of the quantum system a significant challenge. Machine learning technique has brought apparent advantages in some learning strategies, therefore, we introduce it to indirect learning in this paper. Based on Choi-Jamiolkowski isomorphism, we propose a protocol that learns the dynamics of an inaccessible quantum system using a quantum device at hand. For an n-qubit system, the learning task can be done iteratively, with operational complexity O(poly(n,L)/ε2) in each iteration, where L is the circuit depth and ε is the measurement error. Then we theoretically prove its noise resilience to global depolarization, state preparation and measurement noise, and unitary noise in gates implementation, where we find the learned dynamics stay invariant. Finally, we investigate the protocol experimentally on a nitrogen-vacancy center system with a natural noise source. The results show that the behavior of a relatively intractable nuclear spin can be learned through an easily accessible electron spin under different noise models, demonstrating the protocol’s feasibility.","PeriodicalId":508829,"journal":{"name":"New Journal of Physics","volume":"44 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140077724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Weyl points and anomalous transport effects tuned by the Fe doping in Mn3Ge Weyl semimetal 通过在 Mn3Ge Weyl 半金属中掺入铁来调节 Weyl 点和反常输运效应

New Journal of Physics Pub Date : 2024-03-06 DOI: 10.1088/1367-2630/ad309b

V. Rai, Subhadip Jana, Jorg Persson, Shibabrata Nandi

{"title":"Weyl points and anomalous transport effects tuned by the Fe doping in Mn3Ge Weyl semimetal","authors":"V. Rai, Subhadip Jana, Jorg Persson, Shibabrata Nandi","doi":"10.1088/1367-2630/ad309b","DOIUrl":"https://doi.org/10.1088/1367-2630/ad309b","url":null,"abstract":"\u0000 The discovery of a significantly large anomalous Hall effect in the chiral antiferromagnetic system - Mn3Ge- indicates that the Weyl points are widely separated in phase space and positioned near the Fermi surface. Inorder to examine the effects of Fe substitution in Mn3Ge on the presence and location of the Weyl points, we synthesized (Mn1−αFeα)3Ge (α = 0 − 0.30) compounds. The anomalous Hall effect was observed in compounds up to α = 0.22, but only within the temperature range where the magnetic structure remains the same as the Mn3Ge. Additionally, positive longitudinal magnetoconductance and planar Hall effect were detected within the same temperature and doping range. These findings strongly suggest the existence of Weyl points in (Mn1−αFeα)3Ge (α = 0 − 0.22) compounds. Notably, as Fe doping increases, there is a significant reduction in the magnitude of anomalous Hall conductivity, planar Hall effect, and positive longitudinal magnetoconductance, indicating that the Weyl points move further away from the Fermi surface. Consequently, it can be concluded that suitable dopants in the parent Weyl semimetals have the potential to tune the properties of Weyl points and the resulting anomalous electrical transport effects.","PeriodicalId":508829,"journal":{"name":"New Journal of Physics","volume":"85 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140261545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

First-Principles Study on the Electronic Structure of n-Type Magnetic Semiconductor Ba(Zn1-xCox)2As2 n 型磁性半导体 Ba(Zn1-xCox)2As2 电子结构的第一性原理研究

New Journal of Physics Pub Date : 2024-03-06 DOI: 10.1088/1367-2630/ad309f

G. Zhi, Chenchao Xu, Xueqin Zhao, Jinou Dong, Shengli Guo, H. Man, C. Ding, L. Fu, Yilun Gu, Lingfeng Xie, Xun Pan, Chao Cao, F. Ning

{"title":"First-Principles Study on the Electronic Structure of n-Type Magnetic Semiconductor Ba(Zn1-xCox)2As2","authors":"G. Zhi, Chenchao Xu, Xueqin Zhao, Jinou Dong, Shengli Guo, H. Man, C. Ding, L. Fu, Yilun Gu, Lingfeng Xie, Xun Pan, Chao Cao, F. Ning","doi":"10.1088/1367-2630/ad309f","DOIUrl":"https://doi.org/10.1088/1367-2630/ad309f","url":null,"abstract":"\u0000 We perform systematic first-principles calculations on the electronic structure of n-type magnetic semiconductor Ba(Zn1-xCox)2As2 with the facilitation of HSE06 hybrid functional. Supercells are used to consider the doping of Co atoms, and the first-principles band structures are unfolded for clarity. Based on the calculation results, magnetic states is preferred by individual Co atoms doped in Ba(Zn1-xCox)2As2 at diluted limit, and carriers are originated mainly from situations where only one Co atom exists in the nearest neighbor Zn sites out of certain doped Co atoms. The origination of carriers can be explained by the density of states and the unfolded band structure, where it is found that the scattering effects from single Co atom is small but quite large when more Co atoms are located at adjacent Zn sites. The large scattering effects of two adjacent Co atoms will alter the band structures near the Fermi-level. Carriers in Ba(Zn1-xCox)2As2 mainly originate from the As-4p orbitals, with partial contributions from the Co-3d orbitals. Our work provides new insights into the origin of the n-type carriers in magnetic semiconductors and will inspire the development of new magnetic semiconducting systems.","PeriodicalId":508829,"journal":{"name":"New Journal of Physics","volume":"81 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140261588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Eﬀects of band gap on the magic-angle of twisted bilayer graphene 带隙对扭曲双层石墨烯魔角的影响

New Journal of Physics Pub Date : 2024-03-04 DOI: 10.1088/1367-2630/ad3000

Guodong Yu, Lanting Feng

引用次数: 0

Phonon heat removal from metal nano-particles and dynamics of nano-particle cooling at low temperatures 金属纳米粒子的声子散热和纳米粒子低温冷却动力学

New Journal of Physics Pub Date : 2024-03-02 DOI: 10.1088/1367-2630/ad2f69

A. Bezuglyj, L. Davydov

引用次数: 0