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arXiv · 1406.3132

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
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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 quantum Hall 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 the in presence of an interlayer potential U. In the phase space of U and filling factor, we observe an intriguing hexagon pattern, which is accounted for by a model based on crossings between symmetry-broken LLs.

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Y. Lee, D. Tran, K. Myhro, J. Velasco Jr., N. Gillgren, J. M. Poumirol, D. Smirnov, Y. Barlas, C. N. Lau. 2014-06-12. Multicomponent Quantum Hall Ferromagnetism and Landau Level Crossing in Rhombohedral Trilayer Graphene. https://arxiv.org/abs/1406.3132

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