Work

Persistent current states in bilayer graphene

Year: 2015

Type: article

Abstract: We argue that at finite carrier density and large displacement fields, bilayer graphene is prone to $\ensuremath{\ell}=0$ and $\ensuremath{\ell}=1$ Pomeranchuk Fermi-surface instabilities. The broken symmetries are driven by nonlocal exchange interactions which favor momentum-space condensation. We find that electron-electron interactions lead first to spontaneous valley polarization, which breaks time-reversal invariance and is associated with spontaneous orbital magnetism, and then under some circumstances to a nematic phase with reduced rotational symmetry. When present, nematic order is signaled by reduced symmetry in the dependence of optical absorption on light polarization.

Source: Physical Review B

DOI: 10.1103/physrevb.91.155423

Authors: Jeil Jung, Marco Polini, A. H. MacDonald

Institutions: University of Seoul, The University of Texas at Austin, Scuola Normale Superiore, Istituto Nanoscienze, National Enterprise for NanoScience and NanoTechnology

Language: English

Topic: Graphene research and applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Energy, Welch Foundation, Ministero dell’Istruzione, dell’Università e della Ricerca

Awards: G4761632318, G6765329077, G8001030820