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Title: Radiation from electrons in graphene in strong electric field

Abstract

We study the interaction of electrons in graphene with the quantized electromagnetic field in the presence of an applied uniform electric field using the Dirac model of graphene. Electronic states are represented by exact solutions of the Dirac equation in the electric background, and amplitudes of first-order Feynman diagrams describing the interaction with the photon field are calculated for massive Dirac particles in both valleys. Photon emission probabilities from a single electron and from a many-electron system at the charge neutrality point are derived, including the angular and frequency dependence, and several limiting cases are analyzed. The pattern of photon emission at the Dirac point in a strong field is determined by an interplay between the nonperturbative creation of electron–hole pairs and spontaneous emission, allowing for the possibility of observing the Schwinger effect in measurements of the radiation emitted by pristine graphene under DC voltage.

Authors:
Publication Date:
OSTI Identifier:
22403467
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics (New York); Journal Volume: 351; Other Information: Copyright (c) 2014 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; AMPLITUDES; DIRAC EQUATION; ELECTRIC FIELDS; ELECTRIC POTENTIAL; ELECTROMAGNETIC FIELDS; ELECTRONS; EXACT SOLUTIONS; FEYNMAN DIAGRAM; FREQUENCY DEPENDENCE; GRAPHENE; PARTICLES; PHOTON EMISSION; PHOTONS; PROBABILITY

Citation Formats

Yokomizo, N., E-mail: yokomizo@if.usp.br. Radiation from electrons in graphene in strong electric field. United States: N. p., 2014. Web. doi:10.1016/J.AOP.2014.08.024.
Yokomizo, N., E-mail: yokomizo@if.usp.br. Radiation from electrons in graphene in strong electric field. United States. doi:10.1016/J.AOP.2014.08.024.
Yokomizo, N., E-mail: yokomizo@if.usp.br. 2014. "Radiation from electrons in graphene in strong electric field". United States. doi:10.1016/J.AOP.2014.08.024.
@article{osti_22403467,
title = {Radiation from electrons in graphene in strong electric field},
author = {Yokomizo, N., E-mail: yokomizo@if.usp.br},
abstractNote = {We study the interaction of electrons in graphene with the quantized electromagnetic field in the presence of an applied uniform electric field using the Dirac model of graphene. Electronic states are represented by exact solutions of the Dirac equation in the electric background, and amplitudes of first-order Feynman diagrams describing the interaction with the photon field are calculated for massive Dirac particles in both valleys. Photon emission probabilities from a single electron and from a many-electron system at the charge neutrality point are derived, including the angular and frequency dependence, and several limiting cases are analyzed. The pattern of photon emission at the Dirac point in a strong field is determined by an interplay between the nonperturbative creation of electron–hole pairs and spontaneous emission, allowing for the possibility of observing the Schwinger effect in measurements of the radiation emitted by pristine graphene under DC voltage.},
doi = {10.1016/J.AOP.2014.08.024},
journal = {Annals of Physics (New York)},
number = ,
volume = 351,
place = {United States},
year = 2014,
month =
}
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