Article
Chemistry, Multidisciplinary
Saeid Abedi, Esmaeil Taghizadeh Sisakht, S. Javad Hashemifar, Nima Ghafari Cherati, Ismaeil Abdolhosseini Sarsari, Francois M. Peeters
Summary: This article reports the prediction of Al2B2 and AlB4 monolayers as new 2D nonmagnetic Dirac nodal line semimetals with several novel features. In Al2B2, there is an interesting nodal line enclosing the K point and crossing the Fermi level, showing significant dispersion, providing a new platform to explore exotic properties in dispersive Dirac nodal lines. For the AlB4 monolayer, evidence is provided for a set of 2D nonmagnetic open type-II nodal lines coexisting with superconductivity at a rather high transition temperature, offering a platform for the realization of novel topological features in the 2D limit.
Article
Materials Science, Multidisciplinary
Mingqi Chang, Hao Geng, Li Sheng, D. Y. Xing
Summary: The study provides an analytical investigation of the three-dimensional quantum Hall effect in a thin film of a Weyl semimetal from the perspective of bulk states. Through a topological analysis, it derives the Chern numbers for non-zero magnetic fields, revealing a phase diagram in Weyl semimetals. The research demonstrates the influence of Weyl node alignment and film thickness on quantum Hall plateaus, predicting a unique phase diagram for the QHE in thin film Weyl semimetals.
Article
Materials Science, Multidisciplinary
Sai Satyam Samal, S. Nandy, Kush Saha
Summary: The first-order moment of the Berry curvature, the Berry curvature dipole (BCD), has been found to induce nonlinear current in various materials. In certain systems, low-energy Dirac quasiparticles can lead to a non-zero BCD independent of Dirac velocity. These systems may naturally generate helicity-dependent photocurrent and a second-order thermal response.
Review
Physics, Multidisciplinary
Xiaolong Feng, Jiaojiao Zhu, Weikang Wu, Shengyuan A. Yang
Summary: The field of two-dimensional topological semimetals, emerging at the intersection of two-dimensional materials and topological materials, has been rapidly developing in recent years. This review focuses on basic concepts and material examples, as well as discussing outstanding problems that need to be addressed in future research.
Article
Physics, Multidisciplinary
Sajid Sekh, Ipsita Mandal
Summary: In this paper, the authors investigate the Magnus Hall effect (MHE) in various three-dimensional semimetals, exploring the effects of tilt, anisotropy, and multifold degeneracy. The study reveals that a finite MHE response is possible in materials without time-reversal symmetry (TRS), as long as inversion symmetry is broken to prevent cancellation of the MHE contributions. The research is valuable for understanding transport phenomena and nonlinear Hall effects in experimental measurements.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Physics, Fluids & Plasmas
L. K. Ang, Yee Sin Ang, Ching Hua Lee
Summary: We present the theory of out-of-plane (or vertical) electron thermal-field emission from two-dimensional (2D) semimetals. We show that the current-voltage-temperature characteristic is well captured by a universal scaling relation applicable for broad classes of 2D semimetals. Our findings reveal that band topologies in two spatial dimension are indistinguishable from each other and bear no special signature in electron emission characteristics. These findings provide theoretical foundations for the design of 2D-material-based vacuum nanoelectronics.
PHYSICS OF PLASMAS
(2023)
Article
Materials Science, Multidisciplinary
Chiu Fan Bowen Lo, Hoi Chun Po, Andriy H. Nevidomskyy
Summary: The article examines the conditions under which a superconductor inherits topologically protected nodes from its parent normal state. It shows that in both three-dimensional Weyl semimetals and two-dimensional Dirac semimetals, certain conditions in the pairing matrix structure lead to the existence of nodal structures. These nodes are protected by a one-dimensional winding number. The findings are supported by analytical and numerical analyses using models based on monolayer and twisted bilayer graphene.
Article
Physics, Multidisciplinary
Cristian Mejia-Cortes, Mario Molina
Summary: The study investigates the impact of resonant frequency disorder on the eigenstates and transport of magnetic energy in a two-dimensional array of split-ring resonators. Different behaviors of mean square displacement (MSD) are observed in the presence and absence of disorder, with evidence of sub-diffusive behavior in a correlated disorder window.
Article
Physics, Condensed Matter
Ilias Amanatidis, Ioannis Kleftogiannis
Summary: We study the conductance behavior of 2D Dirac semimetal nanowires in the presence of disorder. It is found that for even nanowire lengths, the conductance takes non-integer values that are independent of the length and persist with weak disorder. This effect is attributed to the scattering effects at the interfaces between the leads and the nanowire, an energy gap in the nanowire for even lengths, and the topological properties of the 2D Dirac semimetal.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
Md. S. Hossain, M. K. Ma, K. A. Villegas-Rosales, Y. J. Chung, L. N. Pfeiffer, K. W. West, K. W. Baldwin, M. Shayegan
Summary: The interplay between the Fermi sea anisotropy, electron-electron interaction, and localization phenomena can give rise to exotic many-body phases. This study reports the observation of an ordered anisotropic Wigner solid in a clean two-dimensional electron system with anisotropic effective mass and Fermi sea.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Amarnath Chakraborty, Guang Bian, Giovanni Vignale
Summary: This study calculates the optical absorption spectra of nonsymmorphic semimetals and finds that the absorption coefficient strongly depends on the anisotropy factor and photon polarization. In the presence of a magnetic field, the absorption coefficient also depends on the mixing angle of the band structure. Furthermore, it is discovered that an in-plane magnetic field can induce a Van Hove singularity in the joint density of states, enhancing the optical absorption in one direction of polarization but not the other.
Article
Materials Science, Multidisciplinary
Yonatan Messica, Dmitri B. Gutman, Pavel M. Ostrovsky
Summary: We study the anomalous Hall effect in a disordered Weyl semimetal and show that the intrinsic contribution is expressed in terms of Berry curvature, while the extrinsic contribution is given by a combination of skewscattering and side-jump terms.
Article
Nanoscience & Nanotechnology
Lirong Wang, Min Zhao, Jianhua Wang, Ying Liu, Guodong Liu, Xiaotian Wang, Gang Zhang, Xiaoming Zhang
Summary: The discipline of topological quantum catalysts (TQCs) is developing, focusing on the application of 2D TQCs in 2D topological semimetals. Cu2Si monolayer is proposed as a superior TQC for hydrogen evolution reaction (HER), showing low Gibbs free energy and adjustable catalytic activity through changing the position of nodal lines. Other 2D nodal line semimetals such as Ti3C2, Cr2S3, ScCl, and CuSe also exhibit high HER performance.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
F. Liu, F. Qu, I Zutic, S. Xie, D. Liu, A. L. A. Fonseca, M. Malard
Summary: This study demonstrates that robust nodal-line semimetals can be achieved in two-dimensional materials by introducing vacancies on the lattice, which is related to nonsymmorphic symmetries.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Physics, Multidisciplinary
K. X. Jia, X. Y. Liu, R. Ma, H. Geng, L. Sheng, D. Y. Xing
Summary: This study investigates the disorder-induced phase transition in a cubic lattice nodal-line semimetal using numerical diagonalization and spectral calculations. Unlike nodal-point semimetals, nodal-line semimetals transition to a diffusive metal phase under infinitely weak disorder. Under strong disorder, the material undergoes a transition from a weakly localized diffusive metal state to an Anderson insulator.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Condensed Matter
Elisabeth Wybo, Michael Knap, Frank Pollmann
Summary: The dynamics of entanglement in a Wannier-Stark many-body localized system coupled to a dephasing environment is investigated, using the third Renyi negativity as an accessible entanglement proxy. This measure captures the characteristic logarithmic growth of interacting localized phases up to intermediate time-scales, providing a tool to distinguish Wannier-Stark MBL from noninteracting Wannier-Stark localization and quantify quantum correlations in mixed-state dynamics.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2022)
Article
Physics, Multidisciplinary
J. Knoerzer, T. Shi, E. Demler, J. Cirac
Summary: By studying trapped-ion quantum systems, we can gain insights into generalized Holstein models and benchmark expensive numerical calculations. Our focus is on simulating many-electron systems and examining the competition between charge-density wave order, fermion pairing, and phase separation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
M. K. Joshi, F. Kranzl, A. Schuckert, I Lovas, C. Maier, R. Blatt, M. Knap, C. F. Roos
Summary: Identifying universal properties of nonequilibrium quantum states is a major challenge in modern physics. In this study, researchers experimentally observed a family of hydrodynamic universality classes in a long-range interacting spin chain system, ranging from normal diffusion to anomalous superdiffusion, and extracted the transport coefficients of the hydrodynamic theory, reflecting the microscopic properties of the system.
Article
Physics, Multidisciplinary
Clemens Kuhlenkamp, Michael Knap, Marcel Wagner, Richard Schmidt, Atac Imamoglu
Summary: In this paper, we theoretically analyze a solid-state analog of Feshbach resonances in two-dimensional semiconductor heterostructures. By tuning the applied electric field, the scattering of excitons and electrons occupying different layers can be resonantly enhanced, leading to the formation of an interlayer Feshbach molecule. This discovery has potential implications for the realization of correlated Bose-Fermi mixtures in bilayer semiconductors.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
A. von Hoegen, M. Fechner, M. Foerst, N. Taherian, E. Rowe, A. Ribak, J. Porras, B. Keimer, M. Michael, E. Demler, A. Cavalleri
Summary: In this study, it is shown that certain lattice vibrations in cuprate high-T-c superconductors can induce transient terahertz reflectivity features suggestive of nonequilibrium superconductivity above the critical temperature. Time-resolved measurements reveal a three-order-of-magnitude amplification of a 2.5-THz electronic mode in driven YBa2Cu3O6+x. Theoretical analysis explains these observations by proposing an amplification mechanism for finite-momentum Josephson plasma polaritons. The study also emphasizes the significance of nonlinear mode mixing in amplifying fluctuating modes above the transition temperature in a wide range of materials.
Article
Physics, Multidisciplinary
N. Darkwah Oppong, G. Pasqualetti, O. Bettermann, P. Zechmann, M. Knap, I Bloch, S. Foelling
Summary: This study observes constrained dynamics in a one-dimensional mass-imbalanced Fermi-Hubbard model. By displacing the trap potential and monitoring the dynamical response of the system, suppressed transport and slow relaxation are identified, with a strong dependence on mass imbalance and interspecies interaction strength.
Article
Materials Science, Multidisciplinary
Johannes Feldmeier, William Witczak-Krempa, Michael Knap
Summary: In this study, we demonstrate how the tracer motion of tagged particles can effectively describe transport in quantum many-body systems with constraints. The conservation of spin patterns in the systems leads to specific dynamical behaviors, such as subdiffusive dynamics and intriguing coexistence phenomena. Our findings provide new insights into the dynamics of constrained lattice models and offer a common framework to understand the behavior of different systems.
Article
Materials Science, Multidisciplinary
Wilhelm Kadow, Laurens Vanderstraeten, Michael Knap
Summary: Quantum spin liquids are fascinating phases of matter with fractionalized spin excitations and unconventional long-range quantum entanglement. This study numerically computes the spectral function of a single hole doped into the half-filled Hubbard model on the triangular lattice, revealing distinct signatures of different phases and providing insights into their low-energy features. The hole spectral function, as measured by angle-resolved photoemission spectroscopy, is suggested as a useful tool for characterizing quantum spin liquids.
Article
Materials Science, Multidisciplinary
Izabella Lovas, Robert Citro, Eugene Demler, Thierry Giamarchi, Michael Knap, Edmond Orignac
Summary: We study a quantum many-body variant of the parametric oscillator using a semiclassical truncated Wigner approximation (TWA) to investigate the driven sine-Gordon model with a modulated tunnel coupling. By comparing different methods, we find that TWA can be used to explore the mode-resolved energy density dynamics and higher-order correlations between modes in the prethermal heating regime.
Article
Materials Science, Multidisciplinary
Elisabeth Wybo, Michael Knap, Alvise Bastianello
Summary: The researchers aim to realize quantum simulators of the sine-Gordon model by interfering two weakly coupled one-dimensional cold atomic gases. They use matrix-product state techniques to numerically characterize the low-energy sector of the system and compare it with the exact field-theory predictions, obtaining quantitative boundaries for the validity of the sine-Gordon description. They provide comprehensive evidence for the emergent field theory by probing its rich spectrum and observing the signatures of integrable dynamics in scattering events.
Article
Materials Science, Multidisciplinary
Philip Zechmann, Alvise Bastianello, Michael Knap
Summary: In this study, we developed a quantum Boltzmann approach applicable to weakly interacting systems, and investigated transport in a one-dimensional Hubbard model with different masses of fermionic species. We found excellent agreement between the quantum Boltzmann equation and numerically exact results, and observed distinct transport behaviors in different scenarios.
Article
Materials Science, Multidisciplinary
Stefan Birnkammer, Annabelle Bohrdt, Fabian Grusdt, Michael Knap
Summary: In this study, we propose a Floquet protocol to realize and characterize interacting topological phases in synthetic quantum systems, and provide experimental and numerical evidence for its effectiveness.
Article
Materials Science, Multidisciplinary
Ansgar G. Burchards, Johannes Feldmeier, Alexander Schuckert, Michael Knap
Summary: The study investigates the coupled dynamics of charge and energy in interacting lattice models with dipole conservation, formulating a generic hydrodynamic theory for this combination of fractonic constraints. By developing a microscopic nonequilibrium quantum field theory, the applicability to the late-time dynamics of a specific bosonic quantum system is numerically verified. Extracting all entries of a generalized diffusion matrix using a self-consistent 1/N approximation, the study determines their dependence on microscopic model parameters and discusses the relation of the results to experiments in ultracold atom quantum simulators.
Article
Materials Science, Multidisciplinary
Julian Boesl, Rohit Dilip, Frank Pollmann, Michael Knap
Summary: In this study, we investigate the Bose-Hubbard model under an effective magnetic field and discover various gapped phases connected to quantum Hall states by using the density matrix renormalization group method. Through the calculation of Hall conductance and extraction of topological entanglement entropy, we identify features compatible with different topological orders and further analyze the entanglement spectrum of topological states at different interaction strengths.
Article
Materials Science, Multidisciplinary
Joaquin F. Rodriguez-Nieva, Alexander Schuckert, Dries Sels, Michael Knap, Eugene Demler
Summary: In this study, we analyze the intrinsic stability of spin spiral states in the two-dimensional Heisenberg model. We find that the SU(2) symmetric point exhibits a dynamic instability caused by energetically favorable transverse deformations in both real and spin space of the spiral order. This instability is universal and applies to systems with any spin number, spiral wave vector, and spiral amplitude. Unlike traditional Landau or modulational instabilities, this instability can be triggered solely by quantum fluctuations. By introducing an easy-plane exchange coupling, we show that the stability boundary continuously interpolates between the modulational instability and the transverse instability.
