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  • Letter
  • Open Access

Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene

Hamed Koochaki Kelardeh, Ulf Saalmann, and Jan M. Rost

  • Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, 01187 Dresden, Germany

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Phys. Rev. Research 4, L022014 – Published 21 April, 2022

DOI: https://doi.org/10.1103/PhysRevResearch.4.L022014

Abstract

We identify and describe how intense short light pulses couple to massless Dirac fermions in two-dimensional systems. The ensuing excitation dynamics exhibits unusual scaling with the wavelength of the light due the linear dispersion of the band structure and the fact that light coupling is efficient only close to the Dirac points. We exploit these features to achieve valley polarization of more than 70% with simple pulse shapes. Thereby, we demonstrate that substantial valley polarization at moderate excitation can be achieved with a suitable linearly polarized pulse in gapless systems. Quantitative results are given for pristine graphene.

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References (30)

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Phys. Rev. Research 4, L022014– Published 21 April, 2022
  • Received 13 August 2021
  • Accepted 5 April 2022
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Open access publication funded by the Max Planck Society.

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