npj Quantum Materials最新文献_第4页

Unconventional broadening of Rashba spin splitting in a Au2Sb surface alloy with periodic structural defects 具有周期性结构缺陷的Au2Sb表面合金Rashba自旋劈裂的非常规展宽

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2025-01-11 DOI: 10.1038/s41535-024-00724-5

Jinbang Hu, Xiansi Wang, Anna Cecilie Åsland, Justin W. Wells

引用次数: 0

Electronic spin susceptibility in metallic strontium titanate 金属钛酸锶的电子自旋磁化率

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2025-01-09 DOI: 10.1038/s41535-024-00722-7

A. Najev, N. Somun, M. Spaić, I. Khayr, M. Greven, A. Klein, M. N. Gastiasoro, D. Pelc

{"title":"Electronic spin susceptibility in metallic strontium titanate","authors":"A. Najev, N. Somun, M. Spaić, I. Khayr, M. Greven, A. Klein, M. N. Gastiasoro, D. Pelc","doi":"10.1038/s41535-024-00722-7","DOIUrl":"https://doi.org/10.1038/s41535-024-00722-7","url":null,"abstract":"Metallic strontium titanate (SrTiO3) is known to have both normal-state and superconducting properties that strongly vary over a wide range of charge carrier densities, but the complex interplay between lattice and electronic degrees of freedom has hindered the development of a clear qualitative description of the observed behavior. A major challenge is to understand how the charge carriers themselves evolve with doping and temperature, with possible polaronic effects and evidence of an effective mass that strongly increases with temperature. Here we use 47,49Ti nuclear magnetic resonance (NMR) to perform a comprehensive study of the electronic spin susceptibility in the metallic state of strontium titanate across the doping-temperature phase diagram. We find a temperature-dependent Knight shift that can be quantitatively understood within a nondegenerate Fermi gas model that fully takes into account the complex band structure of SrTiO3. Our data are consistent with a temperature-independent effective mass, and we show that the behavior of the spin susceptibility is universal in a wide range of temperatures and carrier concentrations. These results provide a microscopic foundation for the understanding of the properties of the unconventional low-density metallic state in strontium titanate and related materials.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"85 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Septuple XBi2Te4 (X=Ge, Sn, Pb) intercalated MnBi2Te4 for realizing interlayer ferromagnetism and quantum anomalous hall effect 7颗XBi2Te4 （X=Ge, Sn, Pb）嵌入MnBi2Te4实现层间铁磁性和量子反常霍尔效应

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2025-01-07 DOI: 10.1038/s41535-024-00723-6

Ruixia Yang, Xiaoxiao Man, Jiahui Peng, Jingjing Zhang, Fei Wang, Fang Wang, Huisheng Zhang, Xiaohong Xu

{"title":"Septuple XBi2Te4 (X=Ge, Sn, Pb) intercalated MnBi2Te4 for realizing interlayer ferromagnetism and quantum anomalous hall effect","authors":"Ruixia Yang, Xiaoxiao Man, Jiahui Peng, Jingjing Zhang, Fei Wang, Fang Wang, Huisheng Zhang, Xiaohong Xu","doi":"10.1038/s41535-024-00723-6","DOIUrl":"https://doi.org/10.1038/s41535-024-00723-6","url":null,"abstract":"Realizing the quantum anomalous Hall effect (QAHE) at high temperatures remains a significant challenge in condensed matter physics. MnBi2Te4, an intrinsic magnetic topological insulator, presents a promising platform for QAHE. However, its inherent interlayer antiferromagnetic coupling hinders practical realization at high temperatures. In this study, we propose a novel approach to achieve interlayer ferromagnetic (FM) coupling in MBT bilayer by intercalating the septuple-layer of topological insulators XBi2Te4 (X=Ge, Sn, Pb). Using first-principles calculations, we demonstrate that the pz orbital of the X atom mediates interactions between interlayer Mn atoms, enabling FM coupling. Monte Carlo simulations predict a magnetic transition temperature of 38 K for the MnBi2Te4/PbBi2Te4/MnBi2Te4 heterostructure. Our band structure and topological analyses confirm the preservation of QAHE in all MnBi2Te4/XBi2Te4/MnBi2Te4 heterostructures, while the MnBi2Te4/PbBi2Te4/MnBi2Te4 heterostructure exhibits a topological band gap of 72 meV, significantly exceeding that of the pure MnBi2Te4 bilayer. Furthermore, a continuum model is developed to elucidate the underlying mechanism of the nontrivial topological states. Our work provides a practical pathway to achieving interlayer FM coupling in MnBi2Te4 bilayers, paving the way for high-temperature QAHE and advancing the development of magnetic topological insulators for quantum and spintronic applications.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"117 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142934908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Connection between f-electron correlations and magnetic excitations in UTe2 UTe2中f电子相关与磁激发的关系

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2025-01-04 DOI: 10.1038/s41535-024-00720-9

Thomas Halloran, Peter Czajka, Gicela Saucedo Salas, Corey E. Frank, Chang-Jong Kang, J. A. Rodriguez-Rivera, Jakob Lass, Daniel G. Mazzone, Marc Janoschek, Gabriel Kotliar, Nicholas P. Butch

{"title":"Connection between f-electron correlations and magnetic excitations in UTe2","authors":"Thomas Halloran, Peter Czajka, Gicela Saucedo Salas, Corey E. Frank, Chang-Jong Kang, J. A. Rodriguez-Rivera, Jakob Lass, Daniel G. Mazzone, Marc Janoschek, Gabriel Kotliar, Nicholas P. Butch","doi":"10.1038/s41535-024-00720-9","DOIUrl":"https://doi.org/10.1038/s41535-024-00720-9","url":null,"abstract":"The detailed anisotropic dispersion of the low-temperature, low-energy magnetic excitations of the candidate spin-triplet superconductor UTe2 is revealed using inelastic neutron scattering. The magnetic excitations emerge from the Brillouin zone boundary at the high symmetry Y and T points and disperse along the crystallographic (hat{b})-axis. In applied magnetic fields to at least μ0H = 11 T along the (hat{c}-{rm{axis}}), the magnetism is found to be field-independent in the (hk0) plane. The scattering intensity is consistent with that expected from U3+/U4+ f-electron spins with preferential orientation along the crystallographic (hat{a})-axis, and a fluctuating magnetic moment of μeff=1.7(5) μB. We propose interband spin excitons arising from f-electron hybridization as a possible origin of the magnetic excitations in UTe2.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"66 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142925144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Chemical versus physical pressure effects on the structure transition of bilayer nickelates 化学与物理压力对双层镍酸盐结构转变的影响

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2025-01-02 DOI: 10.1038/s41535-024-00721-8

Gang Wang, Ningning Wang, Tenglong Lu, Stuart Calder, Jiaqiang Yan, Lifen Shi, Jun Hou, Liang Ma, Lili Zhang, Jianping Sun, Bosen Wang, Sheng Meng, Miao Liu, Jinguang Cheng

{"title":"Chemical versus physical pressure effects on the structure transition of bilayer nickelates","authors":"Gang Wang, Ningning Wang, Tenglong Lu, Stuart Calder, Jiaqiang Yan, Lifen Shi, Jun Hou, Liang Ma, Lili Zhang, Jianping Sun, Bosen Wang, Sheng Meng, Miao Liu, Jinguang Cheng","doi":"10.1038/s41535-024-00721-8","DOIUrl":"https://doi.org/10.1038/s41535-024-00721-8","url":null,"abstract":"The observation of high-Tc superconductivity (HTSC) in concomitant with pressure-induced orthorhombic-tetragonal structural transition in bilayer La3Ni2O7 has sparked hopes of achieving HTSC by stabilizing the tetragonal phase at ambient pressure. Chemical pressure, introduced by replacing La3+ with smaller rare-earth R3+ has been considered as a potential route. However, our experimental and theoretical investigation reveals that such substitutions, despite causing lattice contraction, actually produce stronger orthorhombic distortions, requiring higher pressures for the structural transition. A linear extrapolation of Pc versus the average size of A-site cations (<rA>), yields a putative critical value of <rA>c ≈ 1.23 Å for Pc ≈ 1 bar. The negative correlation between Pc and <rA> indicates that replacing La3+ with smaller R3+ ions is unlikely to reduce Pc to ambient pressure. Instead, substituting La3+ with larger cations like Sr2+ or Ba2+ might be a feasible approach. Our results provide guidance for realizing ambient-pressure HTSC in bilayer nickelates.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"81 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142916858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Pairing at a single Van Hove point 在一个范霍夫点配对

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2024-12-24 DOI: 10.1038/s41535-024-00717-4

Risto Ojajärvi, Andrey V. Chubukov, Yueh-Chen Lee, Markus Garst, Jörg Schmalian

引用次数: 0

Discriminating ferrotoroidic from antiferrotoroidic ground states using a 3d quantum spin sensor 基于三维量子自旋传感器的环形铁基态与反环形铁基态的区分

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2024-12-24 DOI: 10.1038/s41535-024-00712-9

Kieran Hymas, Alessandro Soncini, Kuduva R. Vignesh, Deepanshu Chauhan, Abinash Swain, Sophie L. Benjamin, Dipanti Borah, Maheswaran Shanmugam, Wolfgang Wernsdorfer, Gopalan Rajaraman, Stuart K. Langley, Keith S. Murray

{"title":"Discriminating ferrotoroidic from antiferrotoroidic ground states using a 3d quantum spin sensor","authors":"Kieran Hymas, Alessandro Soncini, Kuduva R. Vignesh, Deepanshu Chauhan, Abinash Swain, Sophie L. Benjamin, Dipanti Borah, Maheswaran Shanmugam, Wolfgang Wernsdorfer, Gopalan Rajaraman, Stuart K. Langley, Keith S. Murray","doi":"10.1038/s41535-024-00712-9","DOIUrl":"https://doi.org/10.1038/s41535-024-00712-9","url":null,"abstract":"Molecular toroidal states have come to the forefront as candidates for next-generation quantum information devices owing to their bistability and protection from weak, short-range magnetic interactions. The protection offered by these non-magnetic vortex spin states proves to be a double-edged sword as inferring their existence in a molecular system has yet to be achieved through experimental means alone. Here, we investigate the anomalous, sickle-shaped, single-crystal magnetisation profile arising in μ-SQUID measurements of a novel CrDy3 molecule. Theoretical modelling supported by ab initio calculations demonstrates that the weak field CrDy3 spin dynamics is resultant from quantum superposition of the CrIII spin states determined by three competing interactions: (i) the alignment of the CrIII magnetic moment to the external magnetic field, (ii) the zero-field splitting of the CrIII ground quartet, and (iii) coupling to the remnant magnetisation of the toroidal ground state in the Dy3 triangle. If zero-field splitting of the central transition metal ion is quenched, it operates as a quantum spin sensor, which can be exploited to experimentally discriminate between ferrotoroidic and antiferrotoroidic ground states in MDy6 double triangle complexes through electron paramagnetic resonance experiments and single-crystal magnetisation measurements with a restricted field sweeping domain.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"48 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142879871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Linear and non-linear response of quadratic Lindbladians 二次Lindbladians的线性和非线性响应

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2024-12-21 DOI: 10.1038/s41535-024-00709-4

Spenser Talkington, Martin Claassen

{"title":"Linear and non-linear response of quadratic Lindbladians","authors":"Spenser Talkington, Martin Claassen","doi":"10.1038/s41535-024-00709-4","DOIUrl":"https://doi.org/10.1038/s41535-024-00709-4","url":null,"abstract":"Quadratic Lindbladians encompass a rich class of dissipative electronic and bosonic quantum systems, which have been predicted to host new and exotic physics. In this study, we develop a Lindblad-Keldysh spectroscopic response formalism for open quantum systems that elucidates their steady-state response properties and dissipative phase transitions via finite-frequency linear and non-linear probes. As illustrative examples, we utilize this formalism to calculate the (1) density and dynamic spin susceptibilities of a boundary driven XY model at and near criticality, (2) linear and non-linear optical responses in Bernal bilayer graphene coupled to dissipative leads, and (3) steady state susceptibilities in a bosonic optical lattice. We find that the XY model spin density wavelength diverges with critical exponent 1/2, and there are gapless dispersive modes in the dynamic spin response that originate from the underlying spin density wave order; additionally the dispersing modes of the weak and ultra-strong dissipation limits exhibit a striking correspondence since the boundary dissipators couple only weakly to the bulk in both cases. In the optical response of the Bernal bilayer, we find that the diamagnetic response can decrease with increasing occupation, as opposed to in closed systems where the response increases monotonically with occupation; we study the effect of second harmonic generation and shift current and find that these responses, forbidden in centrosymmetric closed systems, can manifest in these open systems as a result of dissipation. We compare this formalism to its equilibrium counterpart and draw analogies between these non-interacting open systems and strongly interacting closed systems.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"24 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Topological phase transition in quasi-one-dimensional bismuth iodide Bi4I4 准一维碘化铋Bi4I4的拓扑相变

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2024-12-20 DOI: 10.1038/s41535-024-00711-w

W. X. Zhao, M. Yang, X. Du, Y. D. Li, K. Y. Zhai, Y. Q. Hu, J. F. Han, Y. Huang, Z. K. Liu, Y. G. Yao, J. C. Zhuang, Y. Du, J. J. Zhou, Y. L. Chen, L. X. Yang

{"title":"Topological phase transition in quasi-one-dimensional bismuth iodide Bi4I4","authors":"W. X. Zhao, M. Yang, X. Du, Y. D. Li, K. Y. Zhai, Y. Q. Hu, J. F. Han, Y. Huang, Z. K. Liu, Y. G. Yao, J. C. Zhuang, Y. Du, J. J. Zhou, Y. L. Chen, L. X. Yang","doi":"10.1038/s41535-024-00711-w","DOIUrl":"https://doi.org/10.1038/s41535-024-00711-w","url":null,"abstract":"Quasi-one-dimensional (quasi-1D) bismuth iodide Bi4I4 exhibits versatile topological phases of matter including weak topological insulator (WTI) and higher-order topological insulator (HOTI) phases with high tunability in response to external parameters. In this work, performing laser-based angle-resolved photoemission spectroscopy with submicron spatial resolution (micro-ARPES), we reveal the presence of an energy gap on the (100) surface of the low-temperature α-Bi4I4, providing spectroscopic evidence for the HOTI phase. Conversely, the high-temperature β-Bi4I4 harbors gapless Dirac fermions on the (100) surface alongside gapped states on the (001) surface, thereby establishing a WTI phase. By tracking the temperature evolution of the (100) surface states, we unveil a thermal hysteresis of the surface gap in line with the α-β structural phase transition. Our findings directly evidence a temperature-induced topological phase transition from WTI to HOTI in Bi4I4, which paves the way to its potential applications at room temperature.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"1 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Chiral Floquet engineering on topological fermions in chiral crystals 手性晶体中拓扑费米子的手性Floquet工程

IF 5.7 1区物理与天体物理

npj Quantum Materials Pub Date : 2024-12-19 DOI: 10.1038/s41535-024-00714-7

Benshu Fan, Wenhui Duan, Angel Rubio, Peizhe Tang

{"title":"Chiral Floquet engineering on topological fermions in chiral crystals","authors":"Benshu Fan, Wenhui Duan, Angel Rubio, Peizhe Tang","doi":"10.1038/s41535-024-00714-7","DOIUrl":"https://doi.org/10.1038/s41535-024-00714-7","url":null,"abstract":"The interplay of chiralities in light and quantum matter provides an opportunity to design and manipulate chirality-dependent properties in quantum materials. Herein we report the chirality-dependent Floquet engineering on topological fermions with the high Chern number in chiral crystal CoSi via circularly polarized light (CPL) pumping. Intense light pumping does not compromise the gapless nature of topological fermions in CoSi, but displaces the crossing points in momentum space along the direction of light propagation. The Floquet chirality index is proposed to signify the interplay between the chiralities of topological fermion, crystal, and incident light, which determines the amplitudes and directions of light-induced momentum shifts. Regarding the time-reversal symmetry breaking induced by the CPL pumping, momentum shifts of topological fermions result in the birth of transient anomalous Hall signals in non-magnetic CoSi within an ultrafast time scale, which Mid-infrared (IR) pumping and terahertz (THz) Kerr or Faraday probe spectroscopy could experimentally detect. Our findings provide insights into exploring novel applications in optoelectronic devices by leveraging the degree of freedom of chirality in the non-equilibrium regime.","PeriodicalId":19283,"journal":{"name":"npj Quantum Materials","volume":"115 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142848909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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