Multicomponent Quantum Hall Ferromagnetism and Landau Level Crossing in Rhombohedral Trilayer Graphene

Y Lee; D Tran; K Myhro; J Velasco Jr; N Gillgren; J M Poumirol; D Smirnov; Y Barlas; C N Lau

doi:10.1021/acs.nanolett.5b03574

Multicomponent Quantum Hall Ferromagnetism and Landau Level Crossing in Rhombohedral Trilayer Graphene

Nano Lett. 2016 Jan 13;16(1):227-31. doi: 10.1021/acs.nanolett.5b03574. Epub 2015 Dec 10.

Authors

Y Lee¹, D Tran¹, K Myhro¹, J Velasco Jr¹, N Gillgren¹, J M Poumirol², D Smirnov², Y Barlas¹, C N Lau¹

Affiliations

¹ Department of Physics and Astronomy, University of California, Riverside , Riverside, California 91765, United States.
² National High Magnetic Field Laboratory , Tallahassee, Florida 32310, United States.

PMID: 26636471
DOI: 10.1021/acs.nanolett.5b03574

Abstract

Using transport measurements, we investigate multicomponent quantum Hall (QH) ferromagnetism in dual-gated rhombohedral trilayer graphene (r-TLG) in which the real spin, orbital pseudospin, and layer pseudospins of the lowest Landau level form spontaneous ordering. We observe intermediate QH plateaus, indicating a complete lifting of the degeneracy of the zeroth Landau level (LL) in the hole-doped regime. In charge neutral r-TLG, the orbital degeneracy is broken first, and the layer degeneracy is broken last and only in the presence of an interlayer potential U⊥. In the phase space of U⊥ and filling factor ν, we observe an intriguing "hexagon" pattern, which is accounted for by a model based on crossings between symmetry-broken LLs.

Keywords: Landau level crossing; Quantum Hall ferromagnetism; graphene; rhombohedral stacking; trilayer.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.