Communications Physics最新文献_第4页

Three-dimensional bonding anisotropy of bulk hexagonal metal titanium demonstrated by high harmonic generation 用高谐波产生法证明了体体六方金属钛的三维键合各向异性

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-18 DOI: 10.1038/s42005-024-01906-0

Ikufumi Katayama, Kento Uchida, Kimika Takashina, Akari Kishioka, Misa Kaiho, Satoshi Kusaba, Ryo Tamaki, Ken-ichi Shudo, Masahiro Kitajima, Thien Duc Ngo, Tadaaki Nagao, Jun Takeda, Koichiro Tanaka, Tetsuya Matsunaga

{"title":"Three-dimensional bonding anisotropy of bulk hexagonal metal titanium demonstrated by high harmonic generation","authors":"Ikufumi Katayama, Kento Uchida, Kimika Takashina, Akari Kishioka, Misa Kaiho, Satoshi Kusaba, Ryo Tamaki, Ken-ichi Shudo, Masahiro Kitajima, Thien Duc Ngo, Tadaaki Nagao, Jun Takeda, Koichiro Tanaka, Tetsuya Matsunaga","doi":"10.1038/s42005-024-01906-0","DOIUrl":"10.1038/s42005-024-01906-0","url":null,"abstract":"High harmonic generation (HHG) in solid-state materials is an emerging field of photonics research that can unveil the detailed electronic structure of materials, bond strengths and scattering processes of electrons. Although HHG in semiconducting and insulating materials has been intensively investigated both experimentally and theoretically, metals have rarely been explored because the strong screening effect of high-density free electrons is considered to significantly weaken the HHG signal. Here, we investigated HHG upon infrared excitation in bulk hexagonal metal titanium (Ti), a typical building block for practical lightweight structural materials. By analyzing the polarization dependence, the approach revealed the three-dimensional (3D) anisotropy in the electronic states. The results demonstrated the potential of HHG spectroscopy for characterizing 3D bonding anisotropy in metallic systems that are of fundamental importance for designing lightweight and strong structural materials. High harmonics generation (HHG) is a promising way of investigating electronic structures and anisotropy in materials. The authors demonstrate the observation of HHG in simple structural material, hexagonal metal titanium, and experimentally clarified the anisotropy in the electronic states from the polarization dependence.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-7"},"PeriodicalIF":5.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01906-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142845188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Machine-learning-enhanced automatic spectral characterization of x-ray pulses from a free-electron laser 机器学习增强的自由电子激光器x射线脉冲的自动光谱表征

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-18 DOI: 10.1038/s42005-024-01900-6

Danilo Enoque Ferreira de Lima, Arman Davtyan, Joakim Laksman, Natalia Gerasimova, Theophilos Maltezopoulos, Jia Liu, Philipp Schmidt, Thomas Michelat, Tommaso Mazza, Michael Meyer, Jan Grünert, Luca Gelisio

{"title":"Machine-learning-enhanced automatic spectral characterization of x-ray pulses from a free-electron laser","authors":"Danilo Enoque Ferreira de Lima, Arman Davtyan, Joakim Laksman, Natalia Gerasimova, Theophilos Maltezopoulos, Jia Liu, Philipp Schmidt, Thomas Michelat, Tommaso Mazza, Michael Meyer, Jan Grünert, Luca Gelisio","doi":"10.1038/s42005-024-01900-6","DOIUrl":"10.1038/s42005-024-01900-6","url":null,"abstract":"A reliable characterization of x-ray pulses is critical to optimally exploit advanced photon sources, such as free-electron lasers. In this paper, we present a method based on machine learning, the virtual spectrometer, that improves the resolution of non-invasive spectral diagnostics at the European XFEL by up to 40%, and significantly increases its signal-to-noise ratio. This improves the reliability of quasi-real-time monitoring, which is critical to steer the experiment, as well as the interpretation of experimental outcomes. Furthermore, the virtual spectrometer streamlines and automates the calibration of the spectral diagnostic device, which is otherwise a complex and time-consuming task, by virtue of its underlying detection principles. Additionally, the provision of robust quality metrics and uncertainties enable a transparent and reliable validation of the tool during its operation. A complete characterization of the virtual spectrometer under a diverse set of experimental and simulated conditions is provided in the manuscript, detailing advantages and limits, as well as its robustness with respect to the different test cases. A reliable characterization of x-ray pulses is critical to optimally exploit advanced photon sources, such as free-electron lasers. The authors present a method based on machine learning which improves the resolution and signal-to-noise ratio of the non-invasive spectral diagnostics available at European XFEL, and streamlines its operation.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-8"},"PeriodicalIF":5.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01900-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142845136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Online calibration of deep learning sub-models for hybrid numerical modeling systems 混合数值模拟系统中深度学习子模型的在线标定

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-18 DOI: 10.1038/s42005-024-01880-7

Said Ouala, Bertrand Chapron, Fabrice Collard, Lucile Gaultier, Ronan Fablet

{"title":"Online calibration of deep learning sub-models for hybrid numerical modeling systems","authors":"Said Ouala, Bertrand Chapron, Fabrice Collard, Lucile Gaultier, Ronan Fablet","doi":"10.1038/s42005-024-01880-7","DOIUrl":"10.1038/s42005-024-01880-7","url":null,"abstract":"Defining end-to-end (or online) training schemes for the calibration of neural sub-models in hybrid systems requires working with an optimization problem that involves the solver of the physical equations. Online learning methodologies thus require the numerical model to be differentiable, which is not the case for most modeling systems. To overcome this, we present an efficient and practical online learning approach for hybrid systems. The method, called EGA for Euler Gradient Approximation, assumes an additive neural correction to the physical model, and an explicit Euler approximation of the gradients. We demonstrate that the EGA converges to the exact gradients in the limit of infinitely small time steps. Numerical experiments show significant improvements over offline learning, highlighting the potential of end-to-end learning for hybrid modeling. End-to-end learning in hybrid numerical models involves solving an optimization problem that integrates the model’s solver. In many fields, these solvers are written in low-abstraction programming languages that lack automatic differentiation. This work presents a practical approach to solving the optimization problem by efficiently approximating the gradient of the end-to-end objective function.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-15"},"PeriodicalIF":5.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01880-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142845142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cosmic entanglement sudden birth: expansion-induced entanglement in hydrogen atoms 宇宙纠缠突然诞生：氢原子中的膨胀诱导纠缠

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-18 DOI: 10.1038/s42005-024-01907-z

Yusef Maleki, Alireza Maleki, M. Suhail Zubairy

{"title":"Cosmic entanglement sudden birth: expansion-induced entanglement in hydrogen atoms","authors":"Yusef Maleki, Alireza Maleki, M. Suhail Zubairy","doi":"10.1038/s42005-024-01907-z","DOIUrl":"10.1038/s42005-024-01907-z","url":null,"abstract":"Hydrogen is the most dominant atom in the universe and is considered the main component of baryonic matter. Thus far, the quantum features of the unbounded hydrogen atoms in the background of the universe and the possibility of emerging unique quantum effects, such as entanglement on the cosmological scale, have not been considered. In this work, we demonstrate that the dynamical expansion of the universe leads to the emergence of natural entanglement in the hyperfine structure of atomic hydrogen. Our findings reveal that there exists a critical age for the universe where hydrogen atoms naturally build up entanglement, resulting from the expansion of the universe. More precisely, when the universe reaches the age of about 2.5 × 1018 seconds (about 80 billion years old), the hyperfine structure entanglement in hydrogen atoms naturally takes off, demonstrating a peculiar quantum phenomenon known as entanglement sudden birth. This expansion-induced entanglement becomes maximum at about 3.6 × 1018 seconds (about 115 billion years), after the Big Bang. By analyzing the fate of seed atoms formed in the early universe, this study underscores the significance of unique quantum mechanical features, such as entanglement, on cosmological scales. The authors investigate quantum entanglement in the hyperfine structure of the neutral hydrogen atom in thermal equilibrium with the cosmological microwave background radiation. They demonstrate that when the universe is around 80 billion years old, neutral hydrogen atoms begin to form entangled states, displaying a phenomenon known as entanglement sudden birth.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-6"},"PeriodicalIF":5.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01907-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142845259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hour-glass spectra due to oxygen doping in cobaltates 钴酸盐中的氧掺杂导致的小时玻璃光谱

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-16 DOI: 10.1038/s42005-024-01898-x

W. Peng, H. Guo, W. Schmidt, A. Piovano, H. Luetkens, C.-T. Chen, Z. Hu, A. C. Komarek

{"title":"Hour-glass spectra due to oxygen doping in cobaltates","authors":"W. Peng, H. Guo, W. Schmidt, A. Piovano, H. Luetkens, C.-T. Chen, Z. Hu, A. C. Komarek","doi":"10.1038/s42005-024-01898-x","DOIUrl":"10.1038/s42005-024-01898-x","url":null,"abstract":"The magnetic excitation spectrum of most high-temperature superconducting (HTSC) cuprates is hour-glass shaped. The observation of hour-glass spectra in the isostructural Sr-doped cobaltates La2−xSrxCoO4 gives rise to a deeper understanding of these spectra. So far, hour-glass spectra have been only observed in those systems that evolve from incommensurate magnetic peaks. Here, we report on the appearance of hour-glass spectra in oxygen-doped cobaltates La2CoO4+δ. The high-energy part of the hour-glass spectrum of oxygen doped cobaltates is extremely anisotropic with a very prominent stripe-like appearance not seen that clearly in purely Sr-doped compounds. A charge stripe scenario is evidenced by (polarized) neutron diffraction measurements and also corroborated by spin wave simulations. Our results indicate that charge stripes are the origin of the anisotropic stripe- or diamond-shaped high-energy part of the hour-glass spectrum. A link between hour-glass spectra and charge stripes could be of relevance for the physics in HTSC cuprates. The hour-glass magnetic excitation spectrum is a universal feature of most cuprate high-temperature superconductors, yet the exact origins are still debated. Here, using inelastic neutron scattering techniques, the authors report hour-glass magnetic spectra in an oxygen-doped cobaltate La2CoO4+δ and discuss the potential link with charge stripes and the “diamond-shaped” high energy part of the hour-glass spectrum of this system.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-9"},"PeriodicalIF":5.4,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01898-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142826491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Automatic extraction of fine structural information in angle-resolved photoemission spectroscopy by multi-stage clustering algorithm 基于多阶段聚类算法的角分辨光谱学精细结构信息自动提取

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-06 DOI: 10.1038/s42005-024-01878-1

Lingzhu Bian, Chen Liu, Zhen Zhang, Yingke Huang, Xinyu Pan, Yi Zhang, Jiaou Wang, Pavel Dudin, Jose Avila, Zhesheng Chen, Yuhui Dong

{"title":"Automatic extraction of fine structural information in angle-resolved photoemission spectroscopy by multi-stage clustering algorithm","authors":"Lingzhu Bian, Chen Liu, Zhen Zhang, Yingke Huang, Xinyu Pan, Yi Zhang, Jiaou Wang, Pavel Dudin, Jose Avila, Zhesheng Chen, Yuhui Dong","doi":"10.1038/s42005-024-01878-1","DOIUrl":"10.1038/s42005-024-01878-1","url":null,"abstract":"Unsupervised clustering method has shown strong capabilities in automatically categorizing the ARPES (ARPES: angle-resolved photoemission spectroscopy) spatial mapping dataset. However, there is still room for improvement in distinguishing subtle differences caused by different layers and substrates. Here, we propose a method called Multi-Stage Clustering Algorithm (MSCA). Using the K-means clustering results/metrics for real space in different energy-momentum windows as the input of the second round K-means clustering for momentum space, the energy-momentum windows that exhibit subtle inhomogeneity in real space will be highlighted. It recognizes different types of electronic structures both in real space and momentum space in spatially resolved ARPES dataset. This method can be used to capture the areas of interest, and is especially suitable for samples with complex band dispersions, and can be a practical tool to any high dimensional scientific data analysis. A bottleneck for the analysis of data produced by angle-resolved photoemission spectroscopy (ARPES) is the size of the data related to spatial resolution. Building on earlier work, the authors present a data processing method that adopts unsupervised machine learning-based tools to improve the accuracy and efficiency when analysing data produced by nano-ARPES measurements.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-8"},"PeriodicalIF":5.4,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01878-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Community detection and anomaly prediction in dynamic networks 动态网络中的社团检测与异常预测

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-05 DOI: 10.1038/s42005-024-01889-y

Hadiseh Safdari, Caterina De Bacco

{"title":"Community detection and anomaly prediction in dynamic networks","authors":"Hadiseh Safdari, Caterina De Bacco","doi":"10.1038/s42005-024-01889-y","DOIUrl":"10.1038/s42005-024-01889-y","url":null,"abstract":"Anomaly detection is an essential task in the analysis of dynamic networks, offering early warnings of abnormal behavior. We present a principled approach to detect anomalies in dynamic networks that integrates community structure as a foundational model for regular behavior. Our model identifies anomalies as irregular edges while capturing structural changes. Our approach leverages a Markovian framework for temporal transitions and latent variables for community and anomaly detection, inferring hidden parameters to detect unusual interactions. Evaluations on synthetic and real-world datasets show strong anomaly detection across various scenarios. In a case study on professional football player transfers, we detect patterns influenced by club wealth and country, as well as unexpected transactions both within and across community boundaries. This work provides a framework for adaptable anomaly detection, highlighting the value of integrating domain knowledge with data-driven techniques for improved interpretability and robustness in complex networks. The authors propose a method to detect anomalies in dynamic networks by using community structure as a baseline for normal behavior: the model flags anomalies as irregular connections while tracking structural changes. In football player transfers, it reveals patterns tied to club wealth, nationality, and unexpected transactions across communities.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-10"},"PeriodicalIF":5.4,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01889-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Topological superconductivity in monolayer Td−MoTe2 单层Td−MoTe2的拓扑超导性

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-05 DOI: 10.1038/s42005-024-01881-6

Xin-Zhi Li, Zhen-Bo Qi, Quansheng Wu, Wen-Yu He

{"title":"Topological superconductivity in monolayer Td−MoTe2","authors":"Xin-Zhi Li, Zhen-Bo Qi, Quansheng Wu, Wen-Yu He","doi":"10.1038/s42005-024-01881-6","DOIUrl":"10.1038/s42005-024-01881-6","url":null,"abstract":"Topological superconductivity has attracted significant attention due to its potential applications in quantum computation, but its experimental realization remains challenging. Recently, monolayer Td−MoTe2 was observed to exhibit gate tunable superconductivity, and its in-plane upper critical field exceeds the Pauli limit. Here, we show that an in-plane magnetic field beyond the Pauli limit can drive the superconducting monolayer Td−MoTe2 into a topological superconductor. The topological superconductivity arises from the interplay between the in-plane Zeeman coupling and the unique Ising plus in-plane spin-orbit coupling (SOC) in the monolayer Td−MoTe2. The Ising plus in-plane SOC plays the essential role to enable the effective px + ipy pairing. As the essential Ising plus in-plane SOC in the monolayer Td−MoTe2 is generated by an in-plane polar field, our proposal demonstrates that applying an in-plane magnetic field to a gate tunable 2D superconductor with an in-plane polar axis is a feasible way to realize topological superconductivity. Topological superconductivity is the holy grail for implementing fault-tolerant quantum computation. Here, the authors show that for a superconducting monolayer Td−MoTe2 characterized by the Ising plus in-plane spin-orbit coupling, applying an in-plane magnetic field can drive it to a topological superconductor.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-9"},"PeriodicalIF":5.4,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01881-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probing chiral-symmetric higher-order topological insulators with multipole winding number 探测具有多极圈数的手性对称高阶拓扑绝缘子

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-04 DOI: 10.1038/s42005-024-01884-3

Ling Lin, Chaohong Lee

{"title":"Probing chiral-symmetric higher-order topological insulators with multipole winding number","authors":"Ling Lin, Chaohong Lee","doi":"10.1038/s42005-024-01884-3","DOIUrl":"10.1038/s42005-024-01884-3","url":null,"abstract":"The interplay between crystalline symmetry and band topology gives rise to unprecedented lower-dimensional boundary states in higher-order topological insulators (HOTIs). However, the measurement of the topological invariants of HOTIs remains a significant challenge. Here, we define a multipole winding number (MWN) for chiral-symmetric HOTIs by applying a corner twisted boundary condition. The MWN, arising from both bulk and boundary states, accurately captures the bulk-corner correspondence including boundary-obstructed topological phases. To address the measurement challenge, we leverage the perturbative nature of the corner twisted boundary condition and develop a real-space approach for determining the MWN in both two-dimensional and three-dimensional systems. The real-space formula provides an experimentally viable strategy for directly probing the topology of chiral-symmetric HOTIs through dynamical evolution. Our findings not only highlight the twisted boundary condition as a powerful tool for investigating HOTIs, but also establish a paradigm for exploring real-space formulas for the topological invariants of HOTIs. Topological invariants are critical in characterizing higher-order topological insulators. In this work, the authors show how to define a multipole winding number that can capture the bulk-corner correspondence, including boundary obstructed topological phases. An experimental proposal complements the theoretical one.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-9"},"PeriodicalIF":5.4,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01884-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spinor-dominated magnetoresistance in β-Ag2Se β-Ag2Se中旋量主导的磁电阻

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-12-04 DOI: 10.1038/s42005-024-01872-7

Cheng-Long Zhang, Yilin Zhao, Yiyuan Chen, Ziquan Lin, Sen Shao, Zhen-Hao Gong, Junfeng Wang, Hai-Zhou Lu, Guoqing Chang, Shuang Jia

{"title":"Spinor-dominated magnetoresistance in β-Ag2Se","authors":"Cheng-Long Zhang, Yilin Zhao, Yiyuan Chen, Ziquan Lin, Sen Shao, Zhen-Hao Gong, Junfeng Wang, Hai-Zhou Lu, Guoqing Chang, Shuang Jia","doi":"10.1038/s42005-024-01872-7","DOIUrl":"10.1038/s42005-024-01872-7","url":null,"abstract":"A topological insulator is a quantum material which possesses conducting surfaces and an insulating bulk. Despite extensive researches on the properties of Dirac surface states, the characteristics of bulk states have remained largely unexplored. Here we report the observation of spinor-dominated magnetoresistance anomalies in β-Ag2Se, induced by a magnetic-field-driven band topological phase transition. These anomalies are caused by intrinsic orthogonality in the wave-function spinors of the last Landau bands of the bulk states, in which backscattering is strictly forbidden during a band topological phase transition. This new type of longitudinal magnetoresistance, purely controlled by the wave-function spinors of the last Landau bands, highlights a unique signature of electrical transport around the band topological phase transition. With further reducing the quantum limit and gap size in β-Ag2Se, our results may also suggest possible device applications based on this spinor-dominated mechanism and signify a rare case where topology enters the realm of magnetoresistance control. A defining characteristic of non-trivial topological materials is the bulk-boundary correspondence, and the majority of research activities has tended to centre around the surface states. Here, the authors conduct electrical transport measurements on β-Ag2Se observing anomalies in the magnetoresistance measurements, which they contend has a direct connection to the non-trivial topological nature of β-Ag2Se.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-6"},"PeriodicalIF":5.4,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01872-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0