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Title: Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene

Abstract

We discover an unusual phenomenon that occurs when a graphene monolayer is illuminated by a short and intense pulse at normal incidence. Due to the pulse-induced oscillations of the Dirac cones, a dynamical breaking of the layer’s centrosymmetry takes place, leading to the generation of second harmonic waves. We prove that this result can only be found by using the full Dirac equation and show that the widely used semiconductor Bloch equations fail to reproduce this and some other important physics of graphene. Our results open new windows in the understanding of nonlinear light-matter interactions in a wide variety of new 2D materials with a gapped or ungapped Dirac-like dispersion.

Authors:
 [1];  [2];  [1]
  1. School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh (United Kingdom)
  2. ICFO-Institut de Ciencies Fotoniques, 08860 Castelldefels (Barcelona) (Spain)
Publication Date:
OSTI Identifier:
22617478
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics; Journal Volume: 378; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BLOCH EQUATIONS; DIRAC EQUATION; GRAPHENE; HARMONIC GENERATION; HARMONICS; NONLINEAR OPTICS; NONLINEAR PROBLEMS

Citation Formats

Carvalho, David N., Marini, Andrea, and Biancalana, Fabio, E-mail: f.biancalana@hw.ac.uk. Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene. United States: N. p., 2017. Web. doi:10.1016/J.AOP.2016.11.016.
Carvalho, David N., Marini, Andrea, & Biancalana, Fabio, E-mail: f.biancalana@hw.ac.uk. Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene. United States. doi:10.1016/J.AOP.2016.11.016.
Carvalho, David N., Marini, Andrea, and Biancalana, Fabio, E-mail: f.biancalana@hw.ac.uk. Wed . "Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene". United States. doi:10.1016/J.AOP.2016.11.016.
@article{osti_22617478,
title = {Dynamical centrosymmetry breaking — A novel mechanism for second harmonic generation in graphene},
author = {Carvalho, David N. and Marini, Andrea and Biancalana, Fabio, E-mail: f.biancalana@hw.ac.uk},
abstractNote = {We discover an unusual phenomenon that occurs when a graphene monolayer is illuminated by a short and intense pulse at normal incidence. Due to the pulse-induced oscillations of the Dirac cones, a dynamical breaking of the layer’s centrosymmetry takes place, leading to the generation of second harmonic waves. We prove that this result can only be found by using the full Dirac equation and show that the widely used semiconductor Bloch equations fail to reproduce this and some other important physics of graphene. Our results open new windows in the understanding of nonlinear light-matter interactions in a wide variety of new 2D materials with a gapped or ungapped Dirac-like dispersion.},
doi = {10.1016/J.AOP.2016.11.016},
journal = {Annals of Physics},
number = ,
volume = 378,
place = {United States},
year = {Wed Mar 15 00:00:00 EDT 2017},
month = {Wed Mar 15 00:00:00 EDT 2017}
}
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