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Related papers: Intrinsic optical absorption in Dirac metals

200 papers

We present a new theoretical approach to describe X-Ray absorption and Magnetic Circular Dichroism spectra in the presence of e-e correlation. Our approach provides an unified picture to include correlations in both charged and neutral…

Materials Science · Physics 2015-05-20 L. Pardini , V. Bellini , F. Manghi

We show that the gap parameter in \textit{semi}-Dirac material induces a large degree of sensitivity for inter-band optical conductivity with respect to the polarization direction. The optical conductivity reveals an abruptly large value at…

Mesoscale and Nanoscale Physics · Physics 2019-02-20 Alestin Mawrie , Bhaskaran Muralidharan

We compute the optical conductivity for an out-of-plane deformation in graphene using an approach based on solutions of the Dirac equation in curved space. Different examples of periodic deformations along one direction translates into an…

Mesoscale and Nanoscale Physics · Physics 2014-05-05 A. J. Chaves , T. Frederico , O. Oliveira , W. de Paula , M. C. Santos

At photonic Dirac points, electromagnetic waves are governed by the same equations as two-component massless relativistic fermions. However, photonic Dirac points are known to occur in pairs in "photonic graphene" and other similar photonic…

The topological insulator and strong electronic correlation effect are two important subjects in the frontier studies of modern condensed matter physics. A topological insulator exhibits a unique pair of surface conduction bands with the…

Strongly Correlated Electrons · Physics 2015-09-25 Guan Du , Zengyi Du , Xiong Yang , Enyu Wang , Delong Fang , Huan Yang , Hai-Hu Wen

Surface plasmons, which allow extreme confinement of light, suffer from high intrinsic electronic losses. It has been shown that stimulated emission of electrons can transfer energy to plasmons and compensate for the high intrinsic losses.…

Mesoscale and Nanoscale Physics · Physics 2022-12-29 Sang Hyun Park , Michael Sammon , Eugene Mele , Tony Low

We study the photoresponse of two-dimensional semi-Dirac semimetals and three-dimensional Dirac semimetals to off-resonant circularly polarized light. For two-dimensional semi-Dirac semimetals we find that incident light does not open a gap…

Mesoscale and Nanoscale Physics · Physics 2015-06-02 Awadhesh Narayan

ZrSiS exhibits a frequency-independent interband conductivity $\sigma(\omega) = \rm{const}(\omega) \equiv \sigma_{\rm{flat}}$ in a broad range from 250 to 2500 cm$^{-1}$ (30 - 300 meV). This makes ZrSiS similar to (quasi)two-dimensional…

Mesoscale and Nanoscale Physics · Physics 2017-11-03 M. B. Schilling , L. M. Schoop , B. V. Lotsch , M. Dressel , A. V. Pronin

The three-dimensional Dirac semimetal is distinct from its two-dimensional counterpart due to its dimensionality and symmetry. Here, we observe that molecule-based quasi-two-dimensional Dirac fermion system, $\alpha$-(BEDT-TTF)$_2$I$_3$,…

Strongly Correlated Electrons · Physics 2023-11-23 Naoya Tajima , Yoshitaka Kawasugi , Takao Morinari , Ryuhei Oka , Toshio Naito , Reizo Kato

We explore a two-dimensional Hubbard model adapted to host altermagnetic states. Utilizing Hartree-Fock (HF) and dynamical mean field theory (DMFT), we uncover that the magnetic solutions of this model feature Dirac points in their…

Strongly Correlated Electrons · Physics 2025-05-30 Lorenzo Del Re

This study is devoted to the profound implications of tilted Dirac cones on the quantum transport properties of two-dimensional (2D) Dirac materials. These materials, characterized by their linear conic energy dispersions in the vicinity of…

Mesoscale and Nanoscale Physics · Physics 2024-10-30 Rasha Al-Marzoog , Ali Rezaei , Zahra Noorinejad , Mohsen Amini , Ebrahim Ghanbari-Adivi , S. A. Jafari

In this last of three articles on the optical absorption of electrons in a half-filled Peierls-distorted chain we address the dimerized extended Hubbard model in the limit of a large on-site interaction $U$. When the Hubbard interaction is…

Condensed Matter · Physics 2015-06-25 F. Gebhard , K. Bott , M. Scheidler , P. Thomas , S. W. Koch

We compute the effects of strong Hubbardlike local electronic interactions on three-dimensional four-component massless Dirac fermions, which in a noninteracting system possess a microscopic global U(1)$\otimes$SU(2) chiral symmetry. A…

Strongly Correlated Electrons · Physics 2021-01-06 Andras Szabo , Bitan Roy

We present a detailed discussion of extraordinary optoconductance (EOC). Experimental data was acquired via macroscopic metal-semiconductor hybrid structures composed of GaAs and In and subjected to illumination from an Ar ion laser. A…

Materials Science · Physics 2009-11-11 K. A. Wieland , Yun Wang , S. A. Solin , A. M. Girgis , L. R. Ram-Mohan

We report the observation of a light-induced subpicosecond phase transition in the antiferromagnetic Dirac semimetal EuAgAs, achieved through ultrafast optical excitation. Using ultrafast optical spectroscopy, we probe the nonequilibrium…

We investigated the precise crystal structures and electronic states in a quasi-two-dimensional molecular conductor ${\alpha}$-(BETS)$_2$I$_3$ at ambient pressure. The electronic resistivity of this molecular solid shows metal-to-insulator…

The role of absorption in 3D electron diffraction is established through analytical theory, simulation, and dynamical refinement. A two-beam expression for the absorbed integrated intensity is derived, showing that for $t/\xi_g \ll 1$…

Materials Science · Physics 2026-02-10 Benjamin Colmey , Tiarnan A. S. Doherty , Shreshth A. Malik , Paul A. Midgley

While "Dirac cone" dispersions can only be meaningfully defined in two dimensional (2D) systems, the notion of a Dirac point can be extended to three dimensional (3D) classical wave systems. We show that a simple cubic photonic crystal…

Materials Science · Physics 2013-11-01 Xueqin Huang , Fengming Liu , C. T. Chan

It is predicted that electrons on the surface of a topological insulator can acquire a mass (massive Dirac fermion) by opening up a gap at the Dirac point when time-reversal symmetry is broken via the out-of-plane magnetization. We report…

Mesoscale and Nanoscale Physics · Physics 2012-12-17 Su-Yang Xu , L. A. Wray , N. Alidoust , Y. Xia , M. Neupane , Chang Liu , H. -W. Ji , S. Jia , R. J. Cava , M. Z. Hasan

We have carried out the far-infrared transmission measurements on the ligand stabilized Au55 particles dispersed in CsI. We have found that there exists the crossover energy Ec ~ 160 cm -1 (~ 19 meV) beyond which the absorption coefficient…

Mesoscale and Nanoscale Physics · Physics 2013-01-07 Y. H. Kim , Günter Schmid