Journal of Physics: Condensed Matter最新文献

{"title":"Investigation of MoTe nanowires in honeycomb and kagome lattices: Dirac cones and flat bands.","authors":"Túlio V de Oliveira, Guilherme A S Ribeiro, Mario S C Mazzoni","doi":"10.1088/1361-648X/adb5e6","DOIUrl":"10.1088/1361-648X/adb5e6","url":null,"abstract":"<p><p>In this work, we focus on electronic properties of transition-metal monochalcogenide nanowires. Specifically, we apply first-principles calculations to investigate the emergence of Dirac states and flat bands when MoTe nanowires are used as building blocks in kagome and honeycomb lattices. We show that, in spite of being non-covalent, the in-plane interactions of the nanowires are able to reproduce the idiosyncracies associated with these lattices. We describe the contributions of Molybdenium<i>d</i>-orbitals and Tellurium<i>p</i>-orbitals to the electronic states, and we discuss the pivotal role of spin-orbit coupling and of the interwire distances to the phenomenology.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414121","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":"Edge effects in a planar magnet caused by the impact of an electric field.","authors":"E B Magadeev, R M Vakhitov","doi":"10.1088/1361-648X/adb676","DOIUrl":"10.1088/1361-648X/adb676","url":null,"abstract":"<p><p>The paper theoretically studies the effect of a non-uniform electric field on thin ferromagnetic films with a planar distribution of magnetization, which are of interest due to certain possibilities for the formation of vortex-like structures in them and the influence of an electric field is one of the most effective approaches to controlling structures of this type. It is proven that in this case the presence of inhomogeneous magnetoelectric interaction has virtually no effect on the magnetic structure of the sample far from its boundaries, but leads to the appearance of edge effects consisting in the formation of solitary magnetic inhomogeneities at the film boundary. In this case, the structure and properties of such inhomogeneities are completely determined by the values of the electric field potential at the sample boundary. Both for the general case and for a number of specific configurations of the external field, the distribution of magnetization in the region of inhomogeneity is found, and its energy is calculated.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143425534","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":"Ab initio calculations of pressure and temperature dependent elastic constants of lead.","authors":"Camille Jacquelin, Etienne Jaupart, Vincent Dubois, Vanessa Riffet, Philippe Legrand, Laurianne Pillon Pillon","doi":"10.1088/1361-648X/adba2f","DOIUrl":"https://doi.org/10.1088/1361-648X/adba2f","url":null,"abstract":"<p><p>In the framework of DFT, we present a methodology that is as ab initio as possible for calculating the elastic constants in pressure and temperature. In this context, elastic constants are derived via the strain-fluctuation formalism involving Born, kinetic and stress fluctuation terms. AIMD trajectories in the isokinetic (NVT) ensemble are performed using the Abinit software to evaluate each term. Stress fluctuations are obtained directly from the trajectories. The Born term, on the other hand, is obtained by extracting several uncorrelated configurations from the trajectories and applying the energy-strain method. Bayesian inference is used to quantify the uncertainties associated with this procedure. As a result, the methodology enables elastic constants and their uncertainties to be evaluated for a wide range of materials. Admittedly, the whole approach has a high computational cost. In this paper, the method is then applied to solid lead in the fcc and hcp phases at various pressures and temperatures. The elastic constants obtained are linear as a function of temperature and pressure, and are qualitatively consistent with the experimental results available for the fcc phase. The major computational effort involved in obtaining a numerical ab initio reference database for lead can be used to test the accuracy of other approaches using surrogate models.&#xD.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143502049","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":"Magnetodielectric Properties in Two Dimensional Magnetic Insulators.","authors":"Koushik Dey, Hasina Khatun, Anudeepa Ghosh, Soumik Das, Bikash Das, Subhadeep Datta","doi":"10.1088/1361-648X/adb923","DOIUrl":"https://doi.org/10.1088/1361-648X/adb923","url":null,"abstract":"<p><p>Magnetodielectric (MD) materials are important for their ability to spin-charge conversion, magnetic field control of electric polarization and vice versa. Among these, two-dimensional (2D) van der Waals (vdW) magnetic materials are of particular interest due to the presence of magnetic anisotropy (MA) originating from the interaction between the magnetic moments and the crystal field. Also, these materials indicate a high degree of stability in the long-range spin order and may be described using suitable spin Hamiltonians of the Heisenberg, XY, or Ising type. Recent reports have suggested effective interactions between magnetization and electric polarization in 2D magnets. However, MD coupling studies on layered magnetic materials are still few. This review covers the fundamentals of magnetodielectric coupling by explaining related key terms. It includes the necessary conditions for having this coupling and sheds light on the possible physical mechanisms behind this coupling starting from phenomenological descriptions. Apart from that, this review classifies 2D magnetic materials into several categories for reaching out each and every class of materials. Additionally, this review summarizes recent advancements of some pioneer 2D magnetodielectric materials. Last but not the least, the current review provides possible research directions for enhancing magnetodielectric coupling in those and mentions the possibilities for future developments.&#xD.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143472497","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":"Fundamental aspects of Aharonov-Bohm quantum machines: Thermoelectric heatengines and diodes.","authors":"Salil Bedkihal, Jayasmita Behera, Malay Bandyopadhyay","doi":"10.1088/1361-648X/adb921","DOIUrl":"https://doi.org/10.1088/1361-648X/adb921","url":null,"abstract":"<p><p>The study of heat-to-work conversion has gained considerable attention in recent years, highlighting&#xD;the potential of nanoscale systems to achieve energy conversion in steady-state devices without&#xD;the involvement of macroscopic moving parts. The operation of these devices is predicated on the&#xD;steady-state flows of quantum particles, including electrons, photons, and phonons. This review&#xD;examines the theoretical frameworks governing these steady-state flows within various mesoscopic&#xD;or nanoscale devices, such as thermoelectric heat engines, particularly in the context of quantum dot&#xD;Aharonov-Bohm interferometric configurations. Naturally, quantum interference effects hold great&#xD;promise for enhancing the thermoelectric transport properties of these quantum devices by allowing&#xD;more precise control over energy levels and transport pathways, thus improving heat-to-work conversion.&#xD;Driven quantum dot Aharonov-Bohm networks offer an ideal platform for studying these&#xD;engines, thanks to their ability to maintain quantum coherence and provide precise experimental&#xD;control. Unlike bulk systems, nanoscale systems such as quantum dots reveal distinct quantum interference&#xD;phenomena, including sharp features in transmission spectra and Fano resonances. This&#xD;review highlights the distinction between optimization methods that produce boxcar functions and&#xD;coherent control methods that result in complex interference patterns. This review reveals that the&#xD;effective design of thermoelectric heat engines requires careful tailoring of quantum interference and&#xD;the magnetic field-induced effects to enhance performance. In addition, We focus on the fundamental&#xD;questions about the bounds of these thermoelectric machines. Particular emphasis is given to how&#xD;magnetic fields can change the bounds of power or efficiency and the relationship between quantum&#xD;theories of transport and the laws of thermodynamics. These machines with broken time-reversal&#xD;symmetry provides insights into directional dependencies and asymmetries in quantum transport.&#xD;We offer a thorough overview of past and current research on quantum thermoelectric heat engines&#xD;using the Aharonov-Bohm effect and present a detailed review of three-terminal Aharonov-Bohm&#xD;heat engines, where broken time-reversal symmetry can induce a coherent diode effect. Our review&#xD;also covers bounds on power and efficiency in systems with broken time-reversal symmetry. We&#xD;close the review by presenting open questions, summaries, and conclusions.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143472495","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":"Inferring traits of hyperuniformity from local structures via persistent homology.","authors":"Abel H G Milor, Marco Salvalaglio","doi":"10.1088/1361-648X/adb11b","DOIUrl":"10.1088/1361-648X/adb11b","url":null,"abstract":"<p><p>Hyperuniformity refers to the suppression of density fluctuations at large scales. Typical for ordered systems, this property also emerges in several disordered physical and biological systems, where it is particularly relevant to understand mechanisms of pattern formation and to exploit peculiar attributes, e.g. interaction with light and transport phenomena. While hyperuniformity is a global property, ideally defined for infinitely extended systems, several disordered correlated systems have finite size. It has been shown in Salvalaglio<i>et al</i>(2024<i>Phys. Rev. Res.</i><b>6</b>023107) that global hyperuniform (HU) characteristics systematically correlate with distributions of topological properties representative of local arrangements. In this work, building on this information, we explore and assess the inverse relationship between hyperuniformity and local structures in point patterns as described by persistent homology. Standard machine learning algorithms trained on persistence diagrams are shown to detect hyperuniformity of periodic point patterns with high accuracy. Therefore, we demonstrate that the information on patterns' local structures allows for characterizing whether finite size arrangements are analogous to those realized in HU patterns. Then, addressing more quantitative aspects, we show that parameters defining hyperuniformity globally can be reconstructed by comparing persistence diagrams of targeted patterns with reference ones. We also explore the generation of patterns entailing given topological properties. The results of this study pave the way for advanced analysis of HU patterns including local information, and introduce basic concepts for their inverse design.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074548","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":"Existence of structural, electronic and magnetic correlations in Sm₂NiMnO₆double perovskite.","authors":"Supriyo Majumder, Malvika Tripathi, D O de Souza, A Sagdeo, L Olivi, M N Singh, S Pal, D M Phase, R J Choudhary","doi":"10.1088/1361-648X/adb2d1","DOIUrl":"10.1088/1361-648X/adb2d1","url":null,"abstract":"<p><p>Coupling between different interactions allows the control of physical aspects in multifunctional materials by perturbing any degrees of freedom. Here, we aim to probe the correlation among structural, electronic, and magnetic observables in Sm₂NiMnO₆(SNMO) ferromagnetic insulator double perovskite. Our employed methodology includes thermal evolution of x-ray diffraction, x-ray absorption spectroscopy, and bulk magnetometry. The magnetic ordering in SNMO adopts two transitions, at<i>T</i>_C= 160 K due to the ferromagnetic arrangement of Ni-Mn sublattice and at<i>T</i>_d= 34 K because of anti-parallel alignment of polarized Sm paramagnetic moments with respect to Ni-Mn network. Signature of Ni/Mn anti-site disorders are evidenced from short-range structure and magnetization analysis. The long-range as well as short-range crystal structure of SNMO undergo changes across<i>T</i>_Cand<i>T</i>_d, observed through temperature dependent variation in Ni/Mn-O bonding characters. Hybridization between Ni, Mn 3<i>d</i>, O 2<i>p</i>electronic states show changes in the vicinity of magnetic transition. The change in crystal environments governs the magnetic response by imposing alteration in metal-ligand orbital overlap. On the other hand, it is observed that application of electric bias causes monotonic reduction in the saturation magnetic moment. By using these experimental methods, we demonstrate how the structural, electronic, and magnetic properties are correlated in SNMO, which makes it a potential platform for technological usage.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255861","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":"Upper critical fields in high-Tcsuperconductors.","authors":"Wei Wei, Yuling Xiang, Qiang Hou, Yue Sun, Zhixiang Shi","doi":"10.1088/1361-648X/adb2d2","DOIUrl":"10.1088/1361-648X/adb2d2","url":null,"abstract":"<p><p>Since the discovery of high-temperature superconductivity in cuprates, understanding the unconventional pairing mechanism has remained one of the most significant challenges. The upper critical field (Hc2) is an essential parameter for obtaining information on the pair-breaking mechanism, coherence length<i>ξ</i>, and pairing symmetry, all of which are crucial for understanding unconventional superconducting mechanisms. Here, we provide a brief review of studies onHc2in several representative series of cuprate, iron-based, and nickelate superconductors. By comparing the behavior ofHc2as a function of temperature, doping concentration, and anisotropy across these three major classes of superconductors, we hope to contribute to a better understanding of the complex pairing interactions in high-temperature superconductors.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255867","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":"Realizing tunable Fermi level in SnTe by defect control.","authors":"Bamidele Onipede, Matthew Metcalf, Nisha Fletcher, Hui Cai","doi":"10.1088/1361-648X/adb408","DOIUrl":"10.1088/1361-648X/adb408","url":null,"abstract":"<p><p>The tuning of the Fermi level in tin telluride, a topological crystalline insulator, is essential for accessing its unique surface states and optimizing its electronic properties for applications such as spintronics and quantum computing. In this study, we demonstrate that the Fermi level in tin telluride can be effectively modulated by controlling the tin concentration during chemical vapor deposition synthesis. By introducing tin-rich conditions, we observed a blue shift in the x-ray photoelectron spectroscopy core-level peaks of both tin and tellurium, indicating an upward shift in the Fermi level. This shift is corroborated by a decrease in work function values measured via ultraviolet photoelectron spectroscopy, confirming the suppression of Sn vacancies. Our findings provide a low-cost, scalable method to achieve tunable Fermi levels in tin telluride, offering a significant advancement in the development of materials with tailored electronic properties for next-generation technological applications.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143370792","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":"Hydrogen adsorption and properties of goldene: a first-principles study.","authors":"Natalya Sheremetyeva, Vincent Meunier","doi":"10.1088/1361-648X/adb471","DOIUrl":"10.1088/1361-648X/adb471","url":null,"abstract":"<p><p>Goldene, a single-atom Au monolayer with a hexagonal lattice in the P6/mmm space group, exhibits interesting hyrdrogen absorption properties, as revealed using density functional theory calculations. This study focuses on H-adsorbed goldene at different coverage ratios, and provides insights into the energetic and electronic properties of this system, distinguishing it from the well-studied pristine goldene. Hydrogen adsorption on goldene, while energetically comparable to bulk gold, shows a slight reduction in energetic favorability and introduces specific scanning tunneling microscopy images, reported here for the first time. Raman spectra of H-adsorbed goldene at a 1/9 coverage ratio are also first reported here, along with a vibrational mode analysis, highlighting distinct atomic displacement patterns. Finally, for completeness, previously reported results on the dynamical and mechanical stability of pristine goldene are reported, with a special emphasis on the quadratic flexural mode characteristic of 2D materials. New insights into the thermodynamic properties of goldene compared to bulk gold are also discussed. Although bulk gold remains thermodynamically more stable at all temperatures, the vibrational contributions to the Helmholtz free energy favor goldene above 175 K, narrowing the stability gap with temperature. Overall, this study validates goldene's robustness and expands its potential for experimental and theoretical exploration in the context of hydrogen adsorption and functionalized 2D materials more broadly.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143391203","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}