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Related papers: Intrinsic optical absorption in Dirac metals

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Dirac exceptional points (EPs) represent a novel class of non-Hermitian singularities that, unlike conventional EPs, reside entirely within the parity-time unbroken phase and exhibit linear energy dispersion. Here, we theoretically…

Quantum Physics · Physics 2026-04-07 Chia-Yi Ju , Gunnar Möller , Yu-Chin Tzeng

We present a tight binding theory of the Dirac point resonances due to adsorbed atoms and molecules on an infinite 2D graphene sheet based on the standard tight binding model of the graphene p-band electronic structure and the extended…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 S. Ihnatsenka , G. Kirczenow

We analyze the valley selection rules for optical transitions from impurity states to the conduction band in two-dimensional Dirac materials, taking a monolayer of MoS2 as an example. We employ the analytical model of a shallow impurity…

Mesoscale and Nanoscale Physics · Physics 2021-04-14 Dogyun Ko , A. V. Morozov , V. M. Kovalev , I. G. Savenko

Fermi-edge absorption theory predicting the spectrum, A(\omega)\propto \omega^{-2\delta_0/\pi+\delta^2_0/\pi^2}, relies on the assumption that scattering phase, \delta_0, is frequency-independent. Dependence of \delta_0 on \omega becomes…

Mesoscale and Nanoscale Physics · Physics 2011-05-25 V. V. Mkhitaryan , M. E. Raikh

The fermionic dark matter (DM) absorption by nucleus or electron targets provides a distinctive signal to search for sub-GeV DM. We consider a Dirac fermion DM charged under a dark gauge group and with the dark magnetic dipole operator. The…

High Energy Physics - Phenomenology · Physics 2022-06-01 Tong Li , Jiajun Liao , Rui-Jia Zhang

We explore the effect of valley-contrasting gaps in the optical response of two-dimensional anisotropic tilted Dirac systems. We study the spectrum of intraband and interband transitions through the joint density of states (JDOS), the…

Mesoscale and Nanoscale Physics · Physics 2021-04-21 M. A. Mojarro , R. Carrillo-Bastos , Jesús A. Maytorena

We present a theoretical study on the Landau levels (LLs) and magneto-optical absorption of a two-dimensional semi-Dirac electron system under a perpendicular magnetic field. Based on an effective k.p Hamiltonian, we find that the LLs are…

Mesoscale and Nanoscale Physics · Physics 2021-12-07 Xiaoying Zhou , Wang Chen , Xianzhe Zhu

Approaching energy coupling in laser-irradiated metals, we point out the role of electron-electron collision as an efficient control factor for ultrafast optical absorption. The high degree of laser-induced electron-ion nonequilibrium…

The effect of spin-orbit (and Darwin) interaction on a 2D electron gas subject to a radial symmetric, inhomogeneous $1/r$-magnetic field is discussed analytically in a perturbative and non-perturbative manner. For this purpose, we…

Mesoscale and Nanoscale Physics · Physics 2023-06-21 Dominik Sidler , Michael Ruggenthaler , Angel Rubio

Dirac semimetals (DSMs), characterized by linear dispersion relations in their electronic band structure, have gained prominence due to their unique topological features and potential applications in electronic devices. Through systematic…

Materials Science · Physics 2026-03-31 Shivendra Kumar Gupta , Nikhilesh Singh , Saurabh Kumar Sen , Poorva Singh

We study Fermi edge singularities in photo-absorption spectra of generic mesoscopic systems such as quantum dots or nanoparticles. We predict deviations from macroscopic-metallic behavior and propose experimental setups for the observation…

Mesoscale and Nanoscale Physics · Physics 2009-08-12 M. Hentschel , D. Ullmo , H. U. Baranger

Optical conductivity (OC) can serve as a measure of correlation effects in a wide range of condensed matter systems. We here show that the long-range tail of the Coulomb interaction yields a universal correction to the OC in a…

Mesoscale and Nanoscale Physics · Physics 2017-10-18 Bitan Roy , Vladimir Juricic

Dirac semimetals (DSMs) have topologically robust three-dimensional Dirac (doubled Weyl) nodes with Fermi-arc states. In heterostructures involving DSMs, charge transfer occurs at the interfaces, which can be used to probe and control their…

Mesoscale and Nanoscale Physics · Physics 2019-01-30 John W. Villanova , Edwin Barnes , Kyungwha Park

The nonlinear optical properties and electro-optic effects of some oxygen-octahedric ferroelectrics are studied by the density functional theory (DFT) in the local density approximation (LDA) expressions based on first principle…

Materials Science · Physics 2011-12-30 Amirullah M. Mamedov , Ekmel Ozbay

We study spectra of long wavelength plasma oscillations in a system of two energy splitted one-dimensional (1D) massless Dirac fermion subbands coupled by spin-orbit interaction. Such a system may be formed by edge subbands in…

Mesoscale and Nanoscale Physics · Physics 2018-10-24 V. V. Enaldiev

We have calculated the dynamical optical conductivity for $\alpha-\mathcal{T}_3$ materials in the presence of a finite bandgap in their energy bandstructure. This is a special type of energy dispersions because for all…

Materials Science · Physics 2023-05-31 Andrii Iurov , Liubov Zhemchuzhna , Godfrey Gumbs , Danhong Huang

It was recently shown that conventional phonon-electron interactions may induce a triplet pairing state in time-reversal invariant 3D Dirac semi - metals. Starting from the microscopic model of the isotropic Dirac semi-metal, the…

Superconductivity · Physics 2015-04-07 B. Rosenstein , B. Ya. Shapiro , I. Shapiro

Novel two-dimensional (2D) atomically flat materials, such as graphene and transition-metal dichalcogenides, exhibit unconventional Dirac electronic spectra. We propose to effectively engineer their interactions with cold atoms in…

Two-dimensional Dirac semimetal with tilted Dirac cone has recently attracted increasing interest. Tilt of Dirac cone can be realized in a number of materials, including deformed graphene, surface state of topological crystalline insulator,…

Strongly Correlated Electrons · Physics 2018-11-21 Zhao-Kun Yang , Jing-Rong Wang , Guo-Zhu Liu

Dirac semimetals, the materials featured with discrete linearly crossing points (called Dirac points) between four bands, are critical states of topologically distinct phases. Such gapless topological states have been accomplished by a…

Materials Science · Physics 2020-01-20 Xiangxi Cai , Liping Ye , Chunyin Qiu , Meng Xiao , Rui Yu , Manzhu Ke , Zhengyou Liu