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Related papers: Merging of Dirac points in a two-dimensional cryst…

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We analyze the four-dimensional Hamiltonian proposed to describe the band structure of the single-Dirac-cone family of topological insulators in the presence of a uniform perpendicular magnetic field. Surface Landau level(LL) states appear,…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 Zhihua Yang , Jung Hoon Han

We study with first-principles methods the interplay between bulk and surface Dirac fermions in three dimensional Dirac semimetals. By combining density functional theory with the coherent potential approximation, we reveal a topological…

Mesoscale and Nanoscale Physics · Physics 2014-12-18 Awadhesh Narayan , Domenico Di Sante , Silvia Picozzi , Stefano Sanvito

Dirac points in two-dimensional massless Dirac fermions are topologically protected. Although single Dirac point cannot disappear solely, a pair of two Dirac points annihilates after merging at a time-reversal invariant momentum (TRIM).…

Materials Science · Physics 2023-06-27 Keita Kishigi , Keita Tsukidashi , Yasumasa Hasegawa

A Cm planar photonic material (two-dimensional) including the mirror reflection symmetry is explored where in the Dirac cones appeared at the high-symmetry points of the Brillouin zone boundary. By implementing the specific perturbation on…

Applied Physics · Physics 2020-05-26 J. Hajivandi , H. Kurt

The lattice studies in QCD demonstrate the nontrivial localization behavior of the eigenmodes of the 4D Euclidean Dirac operator considered as Hamiltonian of $4+1$ dimensional disordered system. We use the holographic viewpoint to provide…

High Energy Physics - Theory · Physics 2019-07-04 A. Gorsky , M. Litvinov

We show how strongly interacting two-dimensional Dirac fermions can be realized with ultracold atoms in a two-dimensional optical square lattice with an experimentally realistic, inherent gauge field, which breaks time-reversal and…

Quantum Gases · Physics 2015-05-13 Lih-King Lim , Achilleas Lazarides , Andreas Hemmerich , C. Morais Smith

Filling-enforced Dirac semimetals, or those required at specific fillings by the combination of crystalline and time-reversal symmetries, have been proposed and discovered in numerous materials. However, Dirac points in these materials are…

Mesoscale and Nanoscale Physics · Physics 2017-05-26 Steve M Young , Benjamin J. Wieder

Dirac points lie at the heart of many fascinating phenomena in condensed matter physics, from massless electrons in graphene to the emergence of conducting edge states in topological insulators [1, 2]. At a Dirac point, two energy bands…

Quantum Gases · Physics 2013-06-26 Leticia Tarruell , Daniel Greif , Thomas Uehlinger , Gregor Jotzu , Tilman Esslinger

By means of a microwave tight-binding analogue experiment of a graphene-like lattice, we observe a topological transition between a phase with a point-like band gap characteristic of massless Dirac fermions and a gapped phase. By applying a…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Matthieu Bellec , Ulrich Kuhl , Gilles Montambaux , Fabrice Mortessagne

We propose helical topological superconductivity away from the Fermi surface in three-dimensional time-reversal-symmetric odd-parity multiband superconductors. In these systems, pairing between electrons originating from different bands is…

Mesoscale and Nanoscale Physics · Physics 2024-07-01 Masoud Bahari , Song-Bo Zhang , Chang-An Li , Sang-Jun Choi , Philipp Rüßmann , Carsten Timm , Björn Trauzettel

Liquid crystalline phases of matter permeate nature and technology, with examples ranging from cell membranes to liquid-crystal displays. Remarkably, electronic liquid crystal phases can exist in two-dimensional electron systems (2DES) at…

Mesoscale and Nanoscale Physics · Physics 2017-11-20 Q. Qian , J. Nakamura , S. Fallahi , G. C. Gardner , M. J. Manfra

The identification of novel multifunctional Dirac materials has been an ongoing effort. In this connection quasi 2-dimensional (BEDT-TTF)-based charge transfer salts are widely discussed. Here, we report about the electronic structure of…

Materials Science · Physics 2018-08-29 R. Matthias Geilhufe , Benjamin Commeau , Gayanath W. Fernando

Specific properties, such as surface Fermi arcs, features of quantum oscillations and of various responses to a magnetic field, distinguish Dirac semimetals from ordinary materials. These properties are determined by Dirac points at which a…

Mesoscale and Nanoscale Physics · Physics 2024-09-17 Grigorii P. Mikitik

We show that when graphene monolayers are disordered, the conductance exhibits a metallic-to-insulating transition, which opens the door to new electronic devices. The transition can be observed by driving the density or Fermi energy…

Disordered Systems and Neural Networks · Physics 2009-12-07 M. Hilke

We study a non-Hermitian variant of the (2+1)-dimensional Dirac wave equation, which hosts a real energy spectrum with pairwise-orthogonal eigenstates. In the spatially uniform case, the Hamiltonian's non-Hermitian symmetries allow its…

Mesoscale and Nanoscale Physics · Physics 2023-08-09 Yun Yong Terh , Rimi Banerjee , Haoran Xue , Y. D. Chong

In this report we summarize a recent progress in exploration of correlated two-dimensional electron states in partially filled high Landau levels. At a mean-field Hartree-Fock level they can be described as charge-density waves, either…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Michael M. Fogler

Topological properties of Harper and generalized Fibonacci chains are studied in crystalline cases, i.e., for rational values of the modulation frequency. The Harper and Fibonacci crystals at fixed frequency are connected by an…

Mesoscale and Nanoscale Physics · Physics 2018-04-17 Guy Amit , Itzhack Dana

The three dimensional (3D) Dirac semimetal, which has been predicted theoretically, is a new electronic state of matter. It can be viewed as 3D generalization of graphene, with a unique electronic structure in which conduction and valence…

Mesoscale and Nanoscale Physics · Physics 2014-07-10 Sergey Borisenko , Quinn Gibson , Danil Evtushinsky , Volodymyr Zabolotnyy , Bernd Buechner , Robert J. Cava

Two-dimensional (2D) semi-Dirac materials feature a unique anisotropic band structure characterized by quadratic dispersion along one spatial direction and linear dispersion along the other, effectively hybridizing ordinary and Dirac…

Mesoscale and Nanoscale Physics · Physics 2025-10-09 Xin Chen , Jian-Tong Hou , Long Liang , Jie Lu , Hong Guo , Chang-Xu Yan , Hao-Ran Chang

We study electronic structures at an interface between a topological insulator and a ferromagnetic insulator by using three-dimensional two-band model. In usual ferromagnetic insulators, the exchange potential is much larger than the bulk…

Mesoscale and Nanoscale Physics · Physics 2012-11-21 Tetsuro Habe , Yasuhiro Asano