Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.014203
Devendra Singh Bhakuni, Yevgeny Bar Lev
In delocalized systems, particle number fluctuations, also known as quantum surface roughness, and the mean-square displacement exhibit a temporal power law growth followed by a saturation to a system size–dependent value. We use simple scaling arguments to show that these quantities satisfy the Family-Vicsek scaling law and derive a dynamic scaling relation between the dynamical exponents, assuming that the saturation times of both quantities scale similarly with the system size. This relation clarifies the mechanism behind quantum surface roughness growth and suggests that diffusive quantum many-body systems belong to the Edwards-Wilkinson universality class. Moreover, it provides a convenient way to assess quantum transport in cold-atoms experiments. We numerically verify our results by studying two noninteracting models and one interacting model having regimes with distinct dynamical exponents.
{"title":"Dynamic scaling relation in quantum many-body systems","authors":"Devendra Singh Bhakuni, Yevgeny Bar Lev","doi":"10.1103/physrevb.110.014203","DOIUrl":"https://doi.org/10.1103/physrevb.110.014203","url":null,"abstract":"In delocalized systems, particle number fluctuations, also known as quantum surface roughness, and the mean-square displacement exhibit a temporal power law growth followed by a saturation to a system size–dependent value. We use simple scaling arguments to show that these quantities satisfy the Family-Vicsek scaling law and derive a dynamic scaling relation between the dynamical exponents, assuming that the saturation times of both quantities scale similarly with the system size. This relation clarifies the mechanism behind quantum surface roughness growth and suggests that diffusive quantum many-body systems belong to the Edwards-Wilkinson universality class. Moreover, it provides a convenient way to assess quantum transport in cold-atoms experiments. We numerically verify our results by studying two noninteracting models and one interacting model having regimes with distinct dynamical exponents.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141565988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.014202
Ekaterina E. Maslova, Vladislav A. Chistyakov, Mikhail V. Rybin
The transport properties of electromagnetic waves change at the transition of high-index dielectric photonic structures to the metamaterial regime. Here, we demonstrate the changes in the properties of the waves traveling through photonic quasicrystalline structures made of dielectric rods arranged in the nodes on a Penrose tiling lattice with rotation symmetry. We cannot use Bloch theorem in the study of aperiodic structures, so we consider full-scale structures to reveal Bragg- and Mie-type band gaps. A real-space metric allows us to define the period of the effective crystallographic planes in the quasicrystal and to relate the Bragg band gap to the lattice nodes in reciprocal space. We compared the quasicrystal structure with photonic crystals and found that transmission spectra in the band gap have similar profiles for both types of structures. The analysis of the magnetic field distribution in quasicrystal structures with high dielectric permittivity allowed us to recognize near-zero modes, which indicates that the structure acquires the metamaterial regime. The constructed phase diagram specified the metamaterial regime for the structure. Our results reveal the transport properties of photonic quasicrystalline systems in the metamaterial regime.
{"title":"Transport properties of electromagnetic waves in dielectric photonic quasicrystals","authors":"Ekaterina E. Maslova, Vladislav A. Chistyakov, Mikhail V. Rybin","doi":"10.1103/physrevb.110.014202","DOIUrl":"https://doi.org/10.1103/physrevb.110.014202","url":null,"abstract":"The transport properties of electromagnetic waves change at the transition of high-index dielectric photonic structures to the metamaterial regime. Here, we demonstrate the changes in the properties of the waves traveling through photonic quasicrystalline structures made of dielectric rods arranged in the nodes on a Penrose tiling lattice with <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>C</mi><mn>5</mn></msub></math> rotation symmetry. We cannot use Bloch theorem in the study of aperiodic structures, so we consider full-scale structures to reveal Bragg- and Mie-type band gaps. A real-space metric allows us to define the period of the effective crystallographic planes in the quasicrystal and to relate the Bragg band gap to the lattice nodes in reciprocal space. We compared the quasicrystal structure with photonic crystals and found that transmission spectra in the band gap have similar profiles for both types of structures. The analysis of the magnetic field distribution in quasicrystal structures with high dielectric permittivity allowed us to recognize <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>μ</mi></math> near-zero modes, which indicates that the structure acquires the metamaterial regime. The constructed phase diagram specified the metamaterial regime for the structure. Our results reveal the transport properties of photonic quasicrystalline systems in the metamaterial regime.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141565989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.l041301
D. S. Eliseev, A. V. Parafilo, V. M. Kovalev, O. V. Kibis, I. G. Savenko
We develop a theory of a Coulomb interaction-mediated contribution to the valley Hall effect (VHE) in two-dimensional noncentrosymmetric gapped Dirac materials. We assume that the bare valley Hall current occurs in the system due to the presence of disorder caused by impurities and is determined by the valley-selective anisotropic skew scattering. Applying the Boltzmann transport equation to describe the electron and hole transport in the material, we calculate the renormalized VHE conductivity due to electron-electron and electron-hole scattering processes, considering two regimes: (i) an -doped monolayer hosting a degenerate electron gas, and (ii) an intrinsic semiconductor with the Boltzmann statistics of electron and hole gases. In both regimes, the dominant mechanism of interparticle scattering is due to particles residing in different valleys. Moreover, in case (ii), in addition to direct scattering, electron-hole annihilation starts to play a role with the increase in temperature. It might even become the dominant mechanism of the Coulomb interaction-mediated VHE.
我们提出了库仑相互作用介导的二维非新月对称间隙狄拉克材料中山谷霍尔效应（VHE）的理论。我们假定，由于杂质造成的无序存在，系统中会出现裸谷霍尔电流，并由谷选择性各向异性倾斜散射决定。应用玻尔兹曼输运方程来描述材料中的电子和空穴输运，我们计算了电子-电子和电子-空穴散射过程引起的重归一化 VHE 电导率，并考虑了两种情况：(i) 存在退化电子气体的 n 掺杂单层；(ii) 具有电子和空穴气体玻尔兹曼统计量的本征半导体。在这两种情况下，粒子间散射的主要机制都是由于粒子位于不同的山谷中。此外，在第(ii)种情况下，除了直接散射外，随着温度的升高，电子-空穴湮灭也开始发挥作用。它甚至可能成为库仑相互作用介导的 VHE 的主要机制。
{"title":"Renormalization of the valley Hall conductivity due to interparticle interaction","authors":"D. S. Eliseev, A. V. Parafilo, V. M. Kovalev, O. V. Kibis, I. G. Savenko","doi":"10.1103/physrevb.110.l041301","DOIUrl":"https://doi.org/10.1103/physrevb.110.l041301","url":null,"abstract":"We develop a theory of a Coulomb interaction-mediated contribution to the valley Hall effect (VHE) in two-dimensional noncentrosymmetric gapped Dirac materials. We assume that the bare valley Hall current occurs in the system due to the presence of disorder caused by impurities and is determined by the valley-selective anisotropic skew scattering. Applying the Boltzmann transport equation to describe the electron and hole transport in the material, we calculate the renormalized VHE conductivity due to electron-electron and electron-hole scattering processes, considering two regimes: (i) an <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>n</mi></math>-doped monolayer hosting a degenerate electron gas, and (ii) an intrinsic semiconductor with the Boltzmann statistics of electron and hole gases. In both regimes, the dominant mechanism of interparticle scattering is due to particles residing in different valleys. Moreover, in case (ii), in addition to direct scattering, electron-hole annihilation starts to play a role with the increase in temperature. It might even become the dominant mechanism of the Coulomb interaction-mediated VHE.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.024413
Shuyuan Liu, Chongze Wang, Bing Wang, Yu Jia, J. Cho
Mielke and Tasaki's theoretical proposal of flatband ferromagnetism with the Hubbard model has attracted much attention due to the promising possibility of ferromagnetic order in electronic materials. Using first-principles density-functional theory calculations and tight-binding analysis, we present hole-doping-induced flatband ferromagnetism in the van der Waals layered insulating electride material , whose structural framework consists of an array of weakly coupled one-dimensional (1D) Y wires. It is revealed that , featuring a 1D paired, puckered diamond lattice of Y atoms, possesses three occupied valence states: the first- and second-highest ( and ) states give rise to flatbands due to the destructive interference of Bloch wavefunctions, whereas the third-highest () state exhibits a dispersive band along the interstitial space within the paired diamond lattice. Upon partial hole doping of the band with a density larger than 0.3 holes per unit cell, we predict the emergence of ferromagnetism by satisfying the Stoner criterion, enabled by a high density of states at the Fermi level. Interestingly, the spin polarization of the band induces the nearly equal spin splitting of the and bands via the facilitated exchange interactions with the presence of interstitial anionic excess electrons. Our findings offer theoretical insights into an intricate flatband ferromagnetism in the experimentally synthesized 1D electride by hole doping, thereby enriching the family of 1D electride materials for spintronic applications.
{"title":"Flat-band ferromagnetism in the quasi-one-dimensional electride Y2Cl3 induced by hole doping","authors":"Shuyuan Liu, Chongze Wang, Bing Wang, Yu Jia, J. Cho","doi":"10.1103/physrevb.110.024413","DOIUrl":"https://doi.org/10.1103/physrevb.110.024413","url":null,"abstract":"Mielke and Tasaki's theoretical proposal of flatband ferromagnetism with the Hubbard model has attracted much attention due to the promising possibility of ferromagnetic order in electronic materials. Using first-principles density-functional theory calculations and tight-binding analysis, we present hole-doping-induced flatband ferromagnetism in the van der Waals layered insulating electride material <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi mathvariant=\"normal\">Y</mi><mn>2</mn></msub><msub><mi>Cl</mi><mn>3</mn></msub></mrow></math>, whose structural framework consists of an array of weakly coupled one-dimensional (1D) Y wires. It is revealed that <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi mathvariant=\"normal\">Y</mi><mn>2</mn></msub><msub><mi>Cl</mi><mn>3</mn></msub></mrow></math>, featuring a 1D paired, puckered diamond lattice of Y atoms, possesses three occupied valence states: the first- and second-highest (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>1</mn></msub></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>2</mn></msub></math>) states give rise to flatbands due to the destructive interference of Bloch wavefunctions, whereas the third-highest (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>3</mn></msub></math>) state exhibits a dispersive band along the interstitial space within the paired diamond lattice. Upon partial hole doping of the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>1</mn></msub></math> band with a density larger than 0.3 holes per unit cell, we predict the emergence of ferromagnetism by satisfying the Stoner criterion, enabled by a high density of states at the Fermi level. Interestingly, the spin polarization of the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>1</mn></msub></math> band induces the nearly equal spin splitting of the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>2</mn></msub></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>S</mi><mn>3</mn></msub></math> bands via the facilitated exchange interactions with the presence of interstitial anionic excess electrons. Our findings offer theoretical insights into an intricate flatband ferromagnetism in the experimentally synthesized 1D electride <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi mathvariant=\"normal\">Y</mi><mn>2</mn></msub><msub><mi>Cl</mi><mn>3</mn></msub></mrow></math> by hole doping, thereby enriching the family of 1D electride materials for spintronic applications.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141565991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
The coexistence of ferrovalley and band topology has garnered significant attention, due to its valley-polarized quantum anomalous Hall effect in condensed matter physics for two-dimensional (2D) ferromagnetic materials, in which the spontaneous out-of-plane magnetization and strong spin-orbit coupling effect are both satisfied. Here, using first-principles calculations and a tight-binding model, we reported the valley-polarized band topological phase transition and perpendicular magnetocrystalline anisotropy in a series of 2D Janus magnetic transition metal dihalides ( = Ru, Os) via strain manipulation. Due to both the inversion and time-reversal asymmetry, valley polarization could be spontaneously achieved in hexagonal RuClBr and hexagonal OsClBr monolayers, with considerable values of 247 and 150 meV, respectively, which exceed those of most reported 2D ferrovalley materials. By applying an external biaxial strain, it is noteworthy that the easy magnetization axis of -RuClBr can be switched to the out-of-plane direction due to distinct spin channel interactions between the Ru orbitals. Moreover, transitions from the anomalous valley Hall effect to the nontrivial topological state in both -RuClBr and -OsClBr are observed. Due to the spontaneous valley polarization, band topology phase transition, and perpendicular magnetocrystalline anisotropy, it is expected that 2D Janus magnetic transition metal dihalides expand the application for the interplay among valleytronics, spintronics, and band topology.
{"title":"Strain-explorable valley-polarized topological phase transition and perpendicular magnetocrystalline anisotropy in hexagonal MClBr (M = Ru, Os) monolayers","authors":"Zeyu Zhang, He Huang, Liming Wang, Yanzhe Zhao, Chuang Liu, Shiming Zhou, Yanfei Wu, Jiapeng Zhao, Guanxiong Qiao, Dingsong Wang, Jingyan Zhang, Xinqi Zheng, Shouguo Wang","doi":"10.1103/physrevb.110.035128","DOIUrl":"https://doi.org/10.1103/physrevb.110.035128","url":null,"abstract":"The coexistence of ferrovalley and band topology has garnered significant attention, due to its valley-polarized quantum anomalous Hall effect in condensed matter physics for two-dimensional (2D) ferromagnetic materials, in which the spontaneous out-of-plane magnetization and strong spin-orbit coupling effect are both satisfied. Here, using first-principles calculations and a tight-binding model, we reported the valley-polarized band topological phase transition and perpendicular magnetocrystalline anisotropy in a series of 2D Janus magnetic transition metal dihalides <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>H</mi></mrow><mo>−</mo><mrow><mi>M</mi><mi>ClBr</mi></mrow></math> (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>M</mi></mrow></math> = Ru, Os) via strain manipulation. Due to both the inversion and time-reversal asymmetry, valley polarization could be spontaneously achieved in hexagonal RuClBr and hexagonal OsClBr monolayers, with considerable values of 247 and 150 meV, respectively, which exceed those of most reported 2D ferrovalley materials. By applying an external biaxial strain, it is noteworthy that the easy magnetization axis of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>H</mi></mrow></math>-RuClBr can be switched to the out-of-plane direction due to distinct spin channel interactions between the Ru <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>d</mi></math> orbitals. Moreover, transitions from the anomalous valley Hall effect to the nontrivial topological state in both <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>H</mi></mrow></math>-RuClBr and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>H</mi></mrow></math>-OsClBr are observed. Due to the spontaneous valley polarization, band topology phase transition, and perpendicular magnetocrystalline anisotropy, it is expected that 2D Janus magnetic transition metal dihalides expand the application for the interplay among valleytronics, spintronics, and band topology.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.024505
Kirill S. Dubovitskii, Denis M. Basko, Julia S. Meyer, Manuel Houzet
Understanding the mechanisms of qubit decoherence is a crucial prerequisite for improving the qubit performance. In this paper, we discuss the effects of residual Bogolyubov quasiparticles in Schrödinger cat qubits, either of the dissipative or Kerr type. The major difference from previous studies of quasiparticles in superconducting qubits is that the Schrödinger cat qubits are operated under nonequilibrium conditions. Indeed, an external microwave drive is needed to stabilize cat states, which are superpositions of coherent degenerate eigenstates of an effective stationary Lindbladian in the rotating frame. We present a microscopic derivation of the master equation for cat qubits and express the effect of the quasiparticles as dissipators acting on the density matrix of the cat qubit. This enables us to determine the conditions under which the quasiparticles give a substantial contribution to the qubit errors.
{"title":"Theory of quasiparticle-induced errors in driven-dissipative Schrödinger cat qubits","authors":"Kirill S. Dubovitskii, Denis M. Basko, Julia S. Meyer, Manuel Houzet","doi":"10.1103/physrevb.110.024505","DOIUrl":"https://doi.org/10.1103/physrevb.110.024505","url":null,"abstract":"Understanding the mechanisms of qubit decoherence is a crucial prerequisite for improving the qubit performance. In this paper, we discuss the effects of residual Bogolyubov quasiparticles in Schrödinger cat qubits, either of the dissipative or Kerr type. The major difference from previous studies of quasiparticles in superconducting qubits is that the Schrödinger cat qubits are operated under nonequilibrium conditions. Indeed, an external microwave drive is needed to stabilize cat states, which are superpositions of coherent degenerate eigenstates of an effective stationary Lindbladian in the rotating frame. We present a microscopic derivation of the master equation for cat qubits and express the effect of the quasiparticles as dissipators acting on the density matrix of the cat qubit. This enables us to determine the conditions under which the quasiparticles give a substantial contribution to the qubit errors.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.035413
R. Taranko, K. Wrześniewski, I. Weymann, T. Domański
We investigate gradual development of the quasiparticle states in two quantum dots attached to opposite sides of the topological superconducting nanowire, hosting the boundary modes. Specifically, we explore the nonequilibrium cross-correlations transmitted between these quantum dots via the zero-energy Majorana modes. Our analytical and numerical results reveal the nonlocal features observable in the transient behavior of electron pairing, which subsequently cease while the hybrid structure evolves towards its asymptotic steady-state configuration. We estimate duration of these temporary phenomena. Using the nonperturbative scheme of the time-dependent numerical renormalization group technique we also analyze nonequilibrium signatures of the correlation effects competing with the proximity induced electron pairing. These dynamical processes could manifest themselves in braiding protocols imposed on the topological and/or conventional superconducting quantum bits, using superconducting hybrid nanostructures.
{"title":"Transient effects in quantum dots contacted via topological superconductor","authors":"R. Taranko, K. Wrześniewski, I. Weymann, T. Domański","doi":"10.1103/physrevb.110.035413","DOIUrl":"https://doi.org/10.1103/physrevb.110.035413","url":null,"abstract":"We investigate gradual development of the quasiparticle states in two quantum dots attached to opposite sides of the topological superconducting nanowire, hosting the boundary modes. Specifically, we explore the nonequilibrium cross-correlations transmitted between these quantum dots via the zero-energy Majorana modes. Our analytical and numerical results reveal the nonlocal features observable in the transient behavior of electron pairing, which subsequently cease while the hybrid structure evolves towards its asymptotic steady-state configuration. We estimate duration of these temporary phenomena. Using the nonperturbative scheme of the time-dependent numerical renormalization group technique we also analyze nonequilibrium signatures of the correlation effects competing with the proximity induced electron pairing. These dynamical processes could manifest themselves in braiding protocols imposed on the topological and/or conventional superconducting quantum bits, using superconducting hybrid nanostructures.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.014507
Shubham Patel, Soumyasree Jena, A. Taraphder
Utilizing Migdal-Eliashberg theory of superconductivity within the first-principles calculations, we work out the role of electron-phonon coupling (EPC) and anisotropic superconducting properties of a recently discovered [Baidya et al., Phys. Rev. B104, 174510 (2021)] 2D van der Waals heterostructure comprising a single layer of and few layers of . We find strong EPC and a softening of phonon modes in the lowest acoustic branch. While the single layer does not actively contribute to the EPC, it significantly elevates the superconducting critical temperature () compared to monolayer . This is attributed to the degradation of the charge-density wave by the layer. Notably, we observe a two-gap superconductivity in and extend our study to three layers of . A reduction in with increasing thickness of is observed. Incorporation of spin-orbit coupling (SOC) suggests a possible mechanism for Ising superconductivity. We find that SOC reduces EPC while is suppressed concomitantly by about 5K, leading to a closer estimate of the experimental .
{"title":"Electron-phonon coupling, critical temperatures, and gaps in NbSe2/MoS2 Ising superconductors","authors":"Shubham Patel, Soumyasree Jena, A. Taraphder","doi":"10.1103/physrevb.110.014507","DOIUrl":"https://doi.org/10.1103/physrevb.110.014507","url":null,"abstract":"Utilizing Migdal-Eliashberg theory of superconductivity within the first-principles calculations, we work out the role of electron-phonon coupling (EPC) and anisotropic superconducting properties of a recently discovered [Baidya <i>et al.</i>, <span>Phys. Rev. B</span> <b>104</b>, 174510 (2021)] 2D van der Waals heterostructure comprising a single layer of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoS</mi><mn>2</mn></msub></math> and few layers of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NbSe</mi><mn>2</mn></msub></math>. We find strong EPC and a softening of phonon modes in the lowest acoustic branch. While the single <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoS</mi><mn>2</mn></msub></math> layer does not actively contribute to the EPC, it significantly elevates the superconducting critical temperature (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi>c</mi></msub></math>) compared to monolayer <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NbSe</mi><mn>2</mn></msub></math>. This is attributed to the degradation of the charge-density wave by the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoS</mi><mn>2</mn></msub></math> layer. Notably, we observe a two-gap superconductivity in <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi>NbSe</mi><mn>2</mn></msub><mo>/</mo><msub><mi>MoS</mi><mn>2</mn></msub></mrow></math> and extend our study to three layers of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NbSe</mi><mn>2</mn></msub></math>. A reduction in <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi>c</mi></msub></math> with increasing thickness of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NbSe</mi><mn>2</mn></msub></math> is observed. Incorporation of spin-orbit coupling (SOC) suggests a possible mechanism for Ising superconductivity. We find that SOC reduces EPC while <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi>c</mi></msub></math> is suppressed concomitantly by about 5K, leading to a closer estimate of the experimental <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi>c</mi></msub></math>.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.024414
K. A. Muttalib, J. H. Barry
Employing transformations of planar Ising models (decoration-decimation followed by star-triangle), the frustrated antiferromagnetic kagomé Ising model is mapped to the known disordered region of the ferromagnetic triangular Ising model. Thereafter, with supplemental aid of mapping theorems and linear algebraic correlation identities, correlations in the frustrated kagomé Ising model are determined at all temperatures, enabling exact solutions to be obtained in the neutron scattering problem. More particularly, the scattering function is uniform in momentum and exhibits Dirac functions at select scattering frequencies, where each select frequency is associated with a temperature-dependent scattering amplitude. The scattering solutions are compared with those of the ferromagnetic kagomé Ising model.
{"title":"Inelastic neutron scattering from a geometrically frustrated Ising antiferromagnet: Exact solutions","authors":"K. A. Muttalib, J. H. Barry","doi":"10.1103/physrevb.110.024414","DOIUrl":"https://doi.org/10.1103/physrevb.110.024414","url":null,"abstract":"Employing transformations of planar Ising models (decoration-decimation followed by star-triangle), the frustrated antiferromagnetic kagomé Ising model is mapped to the known disordered region of the ferromagnetic triangular Ising model. Thereafter, with supplemental aid of mapping theorems and linear algebraic correlation identities, correlations in the frustrated kagomé Ising model are determined at all temperatures, enabling exact solutions to be obtained in the neutron scattering problem. More particularly, the scattering function <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msup><mi>S</mi><mrow><mi>x</mi><mi>x</mi></mrow></msup><mrow><mo>(</mo><mover accent=\"true\"><mi>q</mi><mo>⃗</mo></mover><mo>,</mo><mi>ω</mi><mo>)</mo></mrow></mrow></math> is uniform in momentum <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mover accent=\"true\"><mi>q</mi><mo>⃗</mo></mover></math> and exhibits Dirac <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>δ</mi></math> functions at select scattering frequencies, where each select frequency is associated with a temperature-dependent scattering amplitude. The scattering solutions are compared with those of the ferromagnetic kagomé Ising model.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-07-10DOI: 10.1103/physrevb.110.014414
Jonas Sonnenschein, Atanu Maity, Chunxiao Liu, Ronny Thomale, Francesco Ferrari, Yasir Iqbal
Motivated by recent numerical studies reporting putative quantum paramagnetic behavior in spin- Heisenberg models on the maple-leaf lattice, we classify Abrikosov fermion mean-field Ansätze of fully symmetric U(1) and quantum spin liquids within the framework of projective symmetry groups. We obtain a total of and algebraic PSGs, and, upon restricting their realization via mean-field Ansätze with nearest-neighbor amplitudes (relevant to the studied models), only 12 U(1) and 8 distinct phases are obtained. We present both singlet and triplet fields for all Ansätze up to third nearest-neighbor bonds and discuss their spinon dispersions as well as their dynamical spin structure factors. We further assess the effects of Gutzwiller projection on the equal-time spin structure factors.
{"title":"Candidate quantum spin liquids on the maple-leaf lattice","authors":"Jonas Sonnenschein, Atanu Maity, Chunxiao Liu, Ronny Thomale, Francesco Ferrari, Yasir Iqbal","doi":"10.1103/physrevb.110.014414","DOIUrl":"https://doi.org/10.1103/physrevb.110.014414","url":null,"abstract":"Motivated by recent numerical studies reporting putative quantum paramagnetic behavior in spin-<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></math> Heisenberg models on the maple-leaf lattice, we classify Abrikosov fermion mean-field <i>Ansätze</i> of fully symmetric U(1) and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi mathvariant=\"double-struck\">Z</mi><mn>2</mn></msub></math> quantum spin liquids within the framework of projective symmetry groups. We obtain a total of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>17</mn><mspace width=\"4pt\"></mspace><mtext>U</mtext><mo>(</mo><mn>1</mn><mo>)</mo></mrow></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>12</mn><mspace width=\"4pt\"></mspace><msub><mi mathvariant=\"double-struck\">Z</mi><mn>2</mn></msub></mrow></math> algebraic PSGs, and, upon restricting their realization via mean-field <i>Ansätze</i> with nearest-neighbor amplitudes (relevant to the studied models), only 12 U(1) and 8 <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi mathvariant=\"double-struck\">Z</mi><mn>2</mn></msub></math> distinct phases are obtained. We present both singlet and triplet fields for all <i>Ansätze</i> up to third nearest-neighbor bonds and discuss their spinon dispersions as well as their dynamical spin structure factors. We further assess the effects of Gutzwiller projection on the equal-time spin structure factors.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141566002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：