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Related papers: Dirac branch-cut modes

200 papers

We study a class of periodic Schr\"odinger operators, which in distinguished cases can be proved to have linear band-crossings or "Dirac points". We then show that the introduction of an "edge", via adiabatic modulation of these periodic…

Mathematical Physics · Physics 2015-04-09 Charles L. Fefferman , James P. Lee-Thorp , Michael I. Weinstein

Beam shaping in nanophotonic systems remains a challenge due to the reliance on complex heuristic optimization procedures. In this work, we experimentally demonstrate a novel approach to topological beam shaping using Jackiw-Rebbi states in…

We study theoretically two-dimensional single-crystalline sheets of semiconductors that form a honeycomb lattice with a period below 10 nm. These systems could combine the usual semiconductor properties with Dirac bands. Using atomistic…

Mesoscale and Nanoscale Physics · Physics 2015-02-19 E. Kalesaki , C. Delerue , C. Morais Smith , W. Beugeling , G. Allan , D. Vanmaekelbergh

We report a unified theory based on linear response, for analyzing the longitudinal optical conductivity (LOC) of materials with tilted Dirac cones. Depending on the tilt parameter $t$, the Dirac electrons have four phases: untilted,…

Mesoscale and Nanoscale Physics · Physics 2023-11-27 Jian-Tong Hou , Chang-Xu Yan , Chao-Yang Tan , Zhi-Qiang Li , Peng Wang , Hong Guo , Hao-Ran Chang

We theoretically propose a design for two-dimensional Dirac semimetals using a bilayer-modified Bernevig-Hughes-Zhang (BHZ) model. By introducing new sites into the BHZ model, we engineer flat bands at the Fermi energy. In the bilayer…

Mesoscale and Nanoscale Physics · Physics 2025-09-08 Lizhou Liu , Cheng-Ming Miao , Qing-Feng Sun , Ying-Tao Zhang

Three-dimensional topological semimetals can support band crossings along one-dimensional curves in the momentum space (nodal lines or Dirac lines) protected by structural symmetries and topology. We consider rhombohedrally (ABC) stacked…

Mesoscale and Nanoscale Physics · Physics 2018-01-15 T. Hyart , R. Ojajärvi , T. T. Heikkilä

Motivated by the results of recent transport and optical conductivity studies, we propose a semi-infinite two-dimensional lattice model for interacting massive Dirac electrons in the pressurized organic conductor…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 Daigo Ohki , Yukiko Omori , Akito Kobayashi

We study three-dimensional Dirac fermions with weak finite-range scalar potential disorder. In the clean system, the density of states vanishes quadratically at the Dirac point. Disorder is known to be perturbatively irrelevant, and…

Statistical Mechanics · Physics 2014-06-12 Rahul Nandkishore , David A. Huse , S. L. Sondhi

We perform a reduction from three to two spatial dimensions of the physics of a spin-1/2 fermion coupled to the electromagnetic field, by applying Hadamard's method of descent. We consider first the free case, in which motion is determined…

Topologically protected wave motion has attracted considerable interest due to its novel properties and potential applications in many different fields. In this work, we study edge modes and traveling edge states via the linear Dirac…

Analysis of PDEs · Mathematics 2022-06-14 Pipi Hu , Peng Xie , Yi Zhu

We investigate some properties of a system of Dirac fermions in 2+1 dimensions, with a space dependent mass having domain wall like defects.These defects are defined by the loci of the points where the mass changes sign. In general, they…

High Energy Physics - Theory · Physics 2009-10-31 C. D. Fosco , A. Lopez

A new class of multi-scale structures, referred to as `parabolic metamaterials' is introduced and studied in this paper. For an elastic two-dimensional triangular lattice, we identify dynamic regimes, which corresponds to so-called `Dirac…

Materials Science · Physics 2016-09-21 D. J. Colquitt , N. V. Movchan , A. B. Movchan

We show that two-dimensional phononic crystals exhibit Dirac cone dispersion at k=0 by exploiting dipole and quadrupole accidental degeneracy. While the equi-frequency surface of Dirac cone modes is isotropic, such systems exhibit…

Materials Science · Physics 2015-05-28 Fengming Liu , Yun Lai , Xueqin Huang , C. T. Chan

We introduce an iterative method to univocally determine the adiabatic expansion of the modes of Dirac fields in spatially homogeneous external backgrounds. We overcome the ambiguities found in previous studies and use this new procedure to…

General Relativity and Quantum Cosmology · Physics 2018-09-20 J. Fernando Barbero G. , Antonio Ferreiro , Jose Navarro-Salas , Eduardo J. S. Villasenor

Based on their formation mechanisms, Dirac points in three-dimensional systems can be classified as accidental or essential. The former can be further distinguished into type-I and type-II, depending on whether the Dirac cone spectrum is…

Materials Science · Physics 2017-09-12 Cong Chen , Shan-Shan Wang , Lei Liu , Zhi-Ming Yu , Xian-Lei Sheng , Ziyu Chen , Shengyuan A. Yang

In this work we study Dirac operators on two-dimensional domains coupled to a magnetic field perpendicular to the plane. We focus on the infinite-mass boundary condition (also called MIT bag condition). In the case of bounded domains, we…

Analysis of PDEs · Mathematics 2021-05-05 Jean-Marie Barbaroux , Loïc Le Treust , Nicolas Raymond , Edgardo Stockmeyer

We consider Dirac quasi-particles, as realized with cold atoms loaded in a honeycomb lattice or in a $\pi$-flux square lattice, in the presence of a weak correlated disorder such that the disorder fluctuations do not couple the two Dirac…

Disordered Systems and Neural Networks · Physics 2014-04-30 Kean Loon Lee , Benoît Grémaud , Christian Miniatura

Many of graphene's unique electronic properties emerge from its Dirac-like electronic energy spectrum. Similarly, it is expected that a nanophotonic system featuring Dirac dispersion will open a path to a number of important research…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 J. Bravo-Abad , J. D. Joannopoulos , M. Soljacic

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

We formulate the Dirac equation for a massive neutral spin-half particle on a rotating black hole spacetime, and we consider its (quasi)bound states: gravitationally-trapped modes which are regular across the future event horizon. These…

General Relativity and Quantum Cosmology · Physics 2015-11-13 Sam R Dolan , David Dempsey