Chiral symmetry breaking by a magnetic field in graphene

KANDEMİR B. S., MOĞULKOÇ A.

PHYSICS LETTERS A, vol.379, no.36, pp.2120-2124, 2015 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 379 Issue: 36
  • Publication Date: 2015
  • Doi Number: 10.1016/j.physleta.2015.06.057
  • Journal Name: PHYSICS LETTERS A
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2120-2124
  • Ankara University Affiliated: Yes

Abstract

We report a novel many-body mechanism for the chiral symmetry breaking in the lowest Landau levels (LLs) of graphene, which is responsible for the new quantum Hall states near the charge neutral Dirac points corresponding to nu = +/- 1 plateaus observed in magnetotransport measurements (Zhang et al., 2006 [31], Jiang et al., 2007 [32]). We show that, when a uniform magnetic field is switched on, valley symmetry breaking emerges in graphene due the interaction of electrons with zone-boundary phonons having A(1g)-symmetry. The induced valley gap is about 14.68 K k(B) root B(T) whose magnitude and field dependence are compatible with the observed quantum Hall plateaus in graphene. (C) 2015 Elsevier B.V. All rights reserved.