{"title":"Anomalous and large topological Hall effects in<i>β</i>-Mn chiral compound Co<sub>6.5</sub>Ru<sub>1.5</sub>Zn<sub>8</sub>Mn<sub>4</sub>: electron electron interaction facilitated quantum interference effect.","authors":"Afsar Ahmed, Arnab Bhattacharya, I Das","doi":"10.1088/1361-648X/ada59f","DOIUrl":"10.1088/1361-648X/ada59f","url":null,"abstract":"<p><p><i>β</i>-Mn-type chiral cubic Co<sub><i>x</i></sub>Zn<sub><i>y</i></sub>Mn<sub><i>z</i></sub>(<i>x</i>+<i>y</i>+<i>z</i>= 20) alloys present a intriguing platform for exploring topological magnetic orderings with promising spintronic potential. This study examines the magnetotransport properties of Co<sub>6.5</sub>Ru<sub>1.5</sub>Zn<sub>8</sub>Mn<sub>4</sub>, a skyrmion-hosting<i>β</i>-Mn-type chiral compound. The longitudinal resistivity (<i>ρ</i><sub><i>xx</i></sub>) exhibits field-insensitive low-temperature minima due to quantum interference effects, driven byT1/2-dependent electron-electron interactions. We observe a substantial intrinsic anomalous Hall conductivity, unaffected by quantum interference. Additionally, a pronounced topological Hall effect is observed at the metastable skyrmionic state, persisting up toTCand achieving notable magnitudes for stoichiometric compounds. These results position the Co<sub><i>x</i></sub>Zn<sub><i>y</i></sub>Mn<sub><i>z</i></sub>family favourably to leverage the rich pallete of emergent magnetotransport properties for spintronic applications.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142927400","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}
Gerhard Gompper, Howard A Stone, Christina Kurzthaler, David Saintillan, Fernado Peruani, Dmitry Fedosov, Thorsten Auth, Cecile Cottin-Bizonne, Christophe Ybert, Eric Clement, Thierry Darnige, Anke Lindner, Raymond E Goldstein, Benno Liebchen, Jack Binysh, Anton Souslov, Lucio Isa, Roberto di Leonardo, Giacomo Frangipane, Hongri Gu, Bradley J Nelson, Fridtjof Brauns, M Cristina Marchetti, Frank Cichos, Veit-Lorenz Heuthe, Clemens Bechinger, Amos Korman, Ofer Feinerman, Andrea Cavagna, Irene Giardina, Hannah Jeckel, Knut Drescher
{"title":"The 2025 Motile Active Matter Roadmap.","authors":"Gerhard Gompper, Howard A Stone, Christina Kurzthaler, David Saintillan, Fernado Peruani, Dmitry Fedosov, Thorsten Auth, Cecile Cottin-Bizonne, Christophe Ybert, Eric Clement, Thierry Darnige, Anke Lindner, Raymond E Goldstein, Benno Liebchen, Jack Binysh, Anton Souslov, Lucio Isa, Roberto di Leonardo, Giacomo Frangipane, Hongri Gu, Bradley J Nelson, Fridtjof Brauns, M Cristina Marchetti, Frank Cichos, Veit-Lorenz Heuthe, Clemens Bechinger, Amos Korman, Ofer Feinerman, Andrea Cavagna, Irene Giardina, Hannah Jeckel, Knut Drescher","doi":"10.1088/1361-648X/adac98","DOIUrl":"https://doi.org/10.1088/1361-648X/adac98","url":null,"abstract":"<p><p>Activity and autonomous motion are fundamental aspects of many living and engineering systems. Here, the scale of biological agents covers a wide range, from nanomotors, cytoskeleton, and cells, to insects, fish, birds, and people. Inspired by biological active systems, various types of autonomous synthetic nano- and micromachines have been designed, which provide the basis for multifunctional, highly responsive, intelligent active materials. A major challenge for understanding and designing active matter is their inherent non-equilibrium nature due to persistent energy consumption, which invalidates equilibrium concepts such as free energy, detailed balance, and time-reversal symmetry. Furthermore, interactions in ensembles of active agents are often non-additive and non-reciprocal. An important aspect of biological agents is their ability to sense the environment, process this information, and adjust their motion accordingly. It is an important goal for the engineering of micro-robotic systems to achieve similar functionality.

With many fundamental properties of motile active matter now reasonably well understood and under control, the ground is prepared for the study of physical aspects and mechanisms of motion in complex environments, of the behavior of systems with new physical features like chirality, of the development of novel micromachines and microbots, of the emergent collective behavior and swarming of intelligent self-propelled particles, and of particular features of microbial systems.

The vast complexity of phenomena and mechanisms involved in the self-organization and dynamics of motile active matter poses major challenges, which can only be addressed by a truly interdisciplinary effort involving scientists from biology, chemistry, ecology, engineering, mathematics, and physics. The 2024 motile active matter roadmap of Journal of Physics: Condensed Matter reviews the current state of the art of the field and provides guidance for further progress in this fascinating research area.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007265","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":"Quantum transport under oscillatory drive with disordered amplitude.","authors":"Vatsana Tiwari, Sushanta Dattagupta, Devendra Singh Bhakuni, Auditya Sharma","doi":"10.1088/1361-648X/adaba9","DOIUrl":"https://doi.org/10.1088/1361-648X/adaba9","url":null,"abstract":"<p><p>We investigate the dynamics of non-interacting particles in a one-dimensional tight-binding chain in the presence of an electric field with random amplitude drawn from a Gaussian distribution, and explicitly focus on the nature of quantum transport. We derive an exact expression for the probability propagator and the mean-squared displacement in the clean limit and generalize it for the disordered case using the Liouville operator method. Our analysis reveals that in the presence a random static field, the system follows diffusive transport; however, an increase in the field strength causes a suppression in the transport and thus asymptotically leads towards localization. We further extend the analysis for a time-dependent disordered electric field and show that the dynamics of mean-squared-displacement deviates from the parabolic path as the field strength increases, unlike the clean limit where ballistic transport occurs.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007224","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":"Terahertz conductivity of two-dimensional materials: a review.","authors":"Shuva Mitra, Laleh Avazpour, Irena Knezevic","doi":"10.1088/1361-648X/adab6a","DOIUrl":"https://doi.org/10.1088/1361-648X/adab6a","url":null,"abstract":"<p><p>Two-dimensional (2D) van der Waals materials are shaping the landscape of next-generation devices, offering significant technological value thanks to their unique, tunable, and layer-dependent electronic and optoelectronic properties. Time-domain spectroscopic techniques at terahertz (THz) frequencies offer noninvasive, contact-free methods for characterizing the dynamics of carriers in 2D materials. They also pave the path toward the applications of 2D materials in detection, imaging, manufacturing, and communication within the increasingly important THz frequency range. In this paper, we overview the synthesis of 2D materials and the prominent THz spectroscopy techniques: THz time-domain spectroscopy (THz-TDS), optical pump THz probe (OPTP) technique, and optical pump--probe (OPP) THz spectroscopy. Through a coalescence of experimental findings, numerical simulation, and theoretical analysis, we present the current understanding of the rich ultrafast physics of technologically significant 2D materials: graphene, transition metal dichalcogenides, MXenes, perovskites, topological 2D materials, and 2D heterostructures. Finally, we offer a perspective on the role of THz characterization in guiding future research and in the quest for ideal 2D materials for new applications.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007160","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":"Enhancing Ω Phase Thermal Stability in Al Alloys through Interstitial Ordering.","authors":"Xiaowei Zhou, Liwen Wang, Chunxuan Liu, Jingwen Qiu, Hongrong Liu, Ziran Liu","doi":"10.1088/1361-648X/ada983","DOIUrl":"https://doi.org/10.1088/1361-648X/ada983","url":null,"abstract":"<p><p>Scandium (Sc) can orderly occupy interstitial sites within the Ω phase of aluminum alloys, forming a new phase that significantly enhances the thermal stability of the alloy. However, Sc is relatively expensive and rare. In this work, we employ first-principles calculations to delve into the physical essence interstitial ordering of Sc in enhancing thermal stability at the electronic level, thereby revealing the crucial factors responsible for this improvement. By computationally screening all potential metallic elements across the periodic table, we uncover that, in addition to Sc, a diverse range of elements including lithium (Li), calcium (Ca), strontium (Sr), and some of rare earth elements (Sm, Ce, Y), possess the potential to contribute to thermal stability enhancement through interstitial ordering mechanisms in aluminum alloys. This study deepens our understanding of microstructural thermal stability and offers novel strategies for designing improved thermally stable Al alloys.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007205","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}
Ken Yaegashi, Katsuaki Sugawara, Takashi Takahashi, Takafumi Sato
{"title":"Role of spin-orbit coupling for the band splitting in ⍺-Sb and ⍺-Bi on SiC(0001).","authors":"Ken Yaegashi, Katsuaki Sugawara, Takashi Takahashi, Takafumi Sato","doi":"10.1088/1361-648X/ada981","DOIUrl":"https://doi.org/10.1088/1361-648X/ada981","url":null,"abstract":"<p><p>Monolayer atomic thin films of group-V elements have a high potential for application in spintronics and valleytronics because of their unique crystal structure and strong spin-orbit coupling. We fabricated Sb and Bi monolayers on a SiC(0001) substrate by the molecular-beam-epitaxy method and studied the electronic structure by angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations. The fabricated Sb film shows the (√3×√3)R30º superstructure associated with the formation of ⍺-Sb, and exhibits a semiconducting nature with a band gap of more than 1.8 eV. Spin-resolved ARPES measurements of isostructural ⍺-Bi revealed the in-plane spin polarization for the topmost valence band, demonstrating its Rashbasplittingof nature due to the space-inversion-symmetry breaking. We discuss the originobserved characteristic band structure and its similarity and difference between Sband Bi.
.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007228","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}
Henrique Felipe Melo, Juliana Brant, Paulo Guimaraes
{"title":"Thickness-dependence of the in-plane thermal conductivity and the interfacial thermal conductance of supported MoS2.","authors":"Henrique Felipe Melo, Juliana Brant, Paulo Guimaraes","doi":"10.1088/1361-648X/ada984","DOIUrl":"https://doi.org/10.1088/1361-648X/ada984","url":null,"abstract":"<p><p>Nowadays, experimental research advances in condensed matter physics are deep-rooted in the development and manipulation of nanomaterials, making it essential to explore the fundamental properties of materials that are candidates for nanotechnology. In this work, we study the dependence of the molybdenum disulfide (MoS2) Raman modes on the sample temperature and on the excitation laser power. From the correlation between these two sets of measurements, we determine the planar thermal conductivity of MoS<sub>2</sub>monolayers, bilayers, trilayers, four layers, seven layers, and eight layers. We find a nonmonotonic behavior, with the thermal conductivity decreasing from 38 Wm-1K-1 to 24 Wm-1K-1, going from monolayer to trilayers, and then increasing from 24 Wm<sup>-1</sup>K<sup>-1</sup>to 50 Wm<sup>-1</sup>K<sup>-1</sup>when the thickness increases from three to eight layers. We associate this behavior with a convolution of two different phonon scattering processes: boundary scattering and interlayer scattering. We also report a monotonic thickness dependence of the interfacial thermal conductance of n-layers of MoS<sub>2</sub>on SiO<sub>2</sub>/Si, which ranges from 0.9 MWm<sup>-2</sup>K<sup>-1</sup>for a monolayer to 3.2 MWm<sup>-2</sup>K<sup>-1</sup>for eight layers films.
.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007268","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}
Olivier Malenfant-Thuot, Dounia Shaaban Kabakibo, Simon Blackburn, Bruno Rousseau, Michel Côté
{"title":"Large scale Raman spectrum calculations in defective 2D materials using deep learning.","authors":"Olivier Malenfant-Thuot, Dounia Shaaban Kabakibo, Simon Blackburn, Bruno Rousseau, Michel Côté","doi":"10.1088/1361-648X/ada106","DOIUrl":"10.1088/1361-648X/ada106","url":null,"abstract":"<p><p>We introduce a machine learning prediction workflow to study the impact of defects on the Raman response of 2D materials. By combining the use of machine-learned interatomic potentials, the Raman-active Γ-weighted density of states method and splitting configurations in independant patches, we are able to reach simulation sizes in the tens of thousands of atoms, with diagonalization now being the main bottleneck of the simulation. We apply the method to two systems, isotopic graphene and defective hexagonal boron nitride, and compare our predicted Raman response to experimental results, with good agreement. Our method opens up many possibilities for future studies of Raman response in solid-state physics.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142854482","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":"Investigation of magnetic and transport properties of GdSbSe.","authors":"Aarti Gautam, Prabuddha Kant Mishra, Souvik Banerjee, A Sundaresan, Ashok Kumar Ganguli","doi":"10.1088/1361-648X/ada50c","DOIUrl":"10.1088/1361-648X/ada50c","url":null,"abstract":"<p><p>We report the detailed investigation of the magnetic, transport, and magnetocaloric effects (MCEs) of GdSbSe by magnetic susceptibilityχ(T), isothermal magnetization<i>M</i>(<i>H</i>), resistivityρ(T,H), and heat capacityCp(T)measurements, crystallizing in the ZrSiS-type tetragonal crystal system with space group P4/nmm. Temperature-dependent magnetic susceptibility measurements revealed long-range antiferromagnetic ordering with two additional magnetic anomalies below Néel temperature (TN≈8.6K), corroborated through magnetocaloric and specific heat studies. Isothermal magnetization measurements unveil hidden metamagnetic signatures through a clear deviation from linearity. In addition, the enhanced value of the Sommerfeld coefficient (<i>γ</i>= 152(5) mJ mol<sup>-1</sup>K<sup>2</sup>) suggests strong electronic correlations in GdSbSe. The entropy of magnetization derived from magnetic isotherms unfolds the field-induced transition from Inverse MCE to Conventional MCE. The detailed transport properties indicate a semimetallic behavior, strongly coupled with magnetic order. Furthermore, the linear field dependence of MR in the high-field region anticipate the possibility of Dirac-like dispersion. Deviations from Kohler's rule and non-linear Hall resistivity suggest the multiband nature of GdSbSe.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142921732","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}
Xueyan Wang, Xin Li, Yang He, Zhen Xu, Haoyang Pan, Jie Li, Yansong Wang, Wenjie Dong, Huamei Chen, Qian Shen, Ziyong Shen, Shimin Hou, Kai Wu, Yajie Zhang, Yongfeng Wang
{"title":"Chirality induced spin selectivity in electron transport investigated by scanning probe microscopy.","authors":"Xueyan Wang, Xin Li, Yang He, Zhen Xu, Haoyang Pan, Jie Li, Yansong Wang, Wenjie Dong, Huamei Chen, Qian Shen, Ziyong Shen, Shimin Hou, Kai Wu, Yajie Zhang, Yongfeng Wang","doi":"10.1088/1361-648X/ada478","DOIUrl":"10.1088/1361-648X/ada478","url":null,"abstract":"<p><p>Chirality induced spin selectivity (CISS) effect implies the relationship between chirality and magnetism, attracting extensive attention in the fields of physics, chemistry and biology. Since it was first discovered with photoemission method in 1999, the CISS effect has been investigated and measured by a variety of methods. Among different means of measurements, scanning probe microscopy (SPM) as a powerful tool to explore the CISS effect, can directly measure and present the spin filtering property of chiral molecules in electron transport. In this paper, we summarize the recent experiments on the CISS effect studied with scanning tunneling microscopy and atomic force microscopy, analyzing the experimental setups and results, and delving into the underlying mechanisms. The present review offers a concise introduction to several chiral molecules which are investigated by SPM for the CISS effect, and a detailed exploration of various experimental techniques tailored to the unique adsorption structures of these molecules. The impact of molecular structure on spin selectivity and the profound implications of CISS are also demonstrated together with a concise overview of CISS theory. A conclusive synopsis and forward-looking perspectives on the investigation of the CISS effect in electron transport utilizing SPM techniques are presented.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142909873","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}