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arXiv · 1602.05031

SU(4) Skyrmions in the $ν=\pm 1$ Quantum Hall State of Graphene

Yunlong Lian·Achim Rosch·Mark O. Goerbig
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Abstract

We explore different skyrmion types in the lowest Landau level of graphene at a filling factor $ν=\pm 1$. In addition to the formation of spin and valley pseudospin skyrmions, we show that another type of spin-valley entangled skyrmions can be stabilized in graphene due to an approximate SU(4) spin-valley symmetry that is affected by sublattice symmetry-breaking terms. These skyrmions have a clear signature in spin-resolved density measurements on the lattice scale, and we discuss the expected patterns for the different skyrmion types.

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Yunlong Lian, Achim Rosch, Mark O. Goerbig. 2016-07-14. SU(4) Skyrmions in the $ν=\pm 1$ Quantum Hall State of Graphene. https://doi.org/10.1103/physrevlett.117.056806

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