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Related papers: Non-Hermitian Dirac cones with valley-dependent li…

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We study the influence of a strong imaginary vector potential on the quantum mechanics of particles confined to a two-dimensional plane and propagating in a random impurity potential. We show that the wavefunctions of the non-Hermitian…

Disordered Systems and Neural Networks · Physics 2009-10-30 Christopher Mudry , B. D. Simons , Alexander Altland

The phenomenon of spin-dependent quantum scattering in two-dimensional (2D) pseudospin-1/2 Dirac materials leading to a relativistic quantum chimera was recently uncovered. We investigate spin-dependent Dirac electron optics in 2D…

Mesoscale and Nanoscale Physics · Physics 2024-08-23 Li-Li Ye , Chen-Di Han , Ying-Cheng Lai

The time evolution of a system with a time-dependent non-Hermitian Hamiltonian is in general unstable with exponential growth or decay. A periodic driving field may stabilize the dynamics because the eigenphases of the associated Floquet…

Quantum Physics · Physics 2015-06-11 Jiangbin Gong , Qing-hai Wang

Non-symmorphic symmetries protect Dirac nodal lines and cones in lattice systems. Here, we investigate the spectral properties of a two-dimensional lattice belonging to a non-symmorphic group. Specifically, we look at the herringbone…

Mesoscale and Nanoscale Physics · Physics 2023-03-09 M. A. J. Herrera , D. Bercioux

We study non-Hermitian photonic lattices that exhibit competition between conservative and non-Hermitian (gain/loss) couplings. A bipartite sublattice symmetry enforces the existence of non-Hermitian flat bands, which are typically embedded…

Optics · Physics 2017-08-30 Daniel Leykam , Sergej Flach , Y. D. Chong

We present a theory of the photovoltaic valley-dependent Hall effect in a two-dimensional Dirac semiconductor subject to an intense near-resonant electromagnetic field. Our theory captures and elucidates the influence of both the…

Mesoscale and Nanoscale Physics · Physics 2018-08-09 V. M. Kovalev , Wang-Kong Tse , M. V. Fistul , I. G. Savenko

Motivated by recent experiments in weakly hybridized small-angle twisted bilayer graphene, we investigate how valley imbalance affects the viscosity of two-dimensional Dirac fluids. We show that shifting the two low-energy Dirac cones…

Mesoscale and Nanoscale Physics · Physics 2026-05-13 Alexey Ermakov , Alessandro Principi

We present the observation of diabolic points in Hermitian and non-Hermitian electronics dimers. The condition of unbreakable Parity-time symmetry is established for both PT-symmetric ZRC and RLC dimers. We show how appears non-Hermitian…

Applied Physics · Physics 2020-05-25 Stéphane Boris Tabeu , Fernande Fotsa-Ngaffo , Aurélien Kenfack-Jiotsa

The periodized cluster dynamical mean-field theory (PCDMFT) combined with exact diagonalization as impurity solver has been applied to the half-filled standard Hubbard model on the honeycomb lattice. A correlated Dirac semimetal is found…

Strongly Correlated Electrons · Physics 2015-10-26 Qing-Xiao Li , Rong-Qiang He , Zhong-Yi Lu

While chirality imbalances are forbidden in conventional lattice systems, non-Hermiticity can effectively avoid the chiral-doubling theorem to facilitate 1D chiral dynamics. Indeed, such systems support unbalanced unidirectional flows that…

Mesoscale and Nanoscale Physics · Physics 2023-03-01 Penghao Zhu , Xiao-Qi Sun , Taylor L. Hughes , Gaurav Bahl

Artificial one- and two-dimensional lattices have emerged as a powerful platform for the emulation of lattice Hamiltonians, the fundamental study of collective many-body effects, and phenomena arising from non-trivial topology.…

Dirac-like cones, featuring conical linear dispersions intersecting with flat bands, typically arise from accidental degeneracy of multiple modes that requires precise tuning of material and structural parameters, inherently limiting their…

Optics · Physics 2025-07-15 Muxuan Yang , Dongyang Yan , Lei Gao , Wei Liu , Yun Lai , Yadong Xu , Zhi Hong Hang , Jie Luo

Non-Hermitian systems with complex-valued energy spectra provide an extraordinary platform for manipulating unconventional dynamics of light. Here, we demonstrate the localization of light in an instantaneously reconfigurable non-Hermitian…

Discrete time crystals (DTC) exhibit a special non-equilibrium phase of matter in periodically driven many-body systems with spontaneous breaking of time translational symmetry. The presence of decoherence generally enhances thermalization…

Quantum Physics · Physics 2024-10-31 Rozhin Yousefjani , Angelo Carollo , Krzysztof Sacha , Saif Al-Kuwari , Abolfazl Bayat

The Dirac fermion with linear dispersion in the kagom\'e lattice governs the low-energy physics of different valleys at two inequivalent corners of hexagonal Brillouin zone. The effective Hamiltonian based on the cyclic permutation symmetry…

Strongly Correlated Electrons · Physics 2025-09-22 Xinyuan Zhou , Ziqiang Wang , Hua Chen

Present computations of the gap of color superconductivity in weak coupling assume that the quarks which participate in the condensation process are infinitely long-lived. However, the quasiparticles in a plasma are characterized by having…

High Energy Physics - Phenomenology · Physics 2009-10-31 Cristina Manuel

We study the effects of non-hermitian perturbation on a quantum kicked model exhibiting a localization transition. Using an exact renormalization scheme, we show that the critical line separating the extended and localized phases approaches…

Disordered Systems and Neural Networks · Physics 2009-11-07 Indubala I satija , Arjendu Pattanayak

In an anti-Hermitian linear system, all energy eigenvalues are purely imaginary and the corresponding eigenvectors are orthogonal. This implies that no stationary state is available in such systems. We consider an anti-Hermitian lattice…

Pattern Formation and Solitons · Physics 2020-01-08 S. Tombuloglu , C. Yuce

Lorentz symmetry appears as a quite robust feature of the strongly interacting Dirac materials even though the lattice interactions break such a symmetry. We here demonstrate that the Lorentz symmetry is restored at the quantum-critical…

Superconductivity · Physics 2024-02-29 Pablo Reiser , Vladimir Juricic

Nonsymmorphic symmetries, which involve fractional lattice translations in crystalline materials, can generate exotic types of fermionic excitations that are robust against spin-orbit coupling. Here we report on a hourglass-type dispersion…

Mesoscale and Nanoscale Physics · Physics 2017-12-08 Shan-Shan Wang , Ying Liu , Zhi-Ming Yu , Xian-Lei Sheng , Shengyuan A. Yang