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Topological insulators with SU(2) Landau levels
Yi Li1, Shou-Cheng Zhang, Congjun Wu
1Department of Physics, University of California, San Diego, La Jolla, California 92093, USA and Princeton Center for Theoretical Science, Princeton University, Princeton, New Jersey 08544, USA.
Abstract:
We construct continuum models of 3D and 4D topological insulators by coupling spin-1/2 fermions to an SU(2) background gauge field, which is equivalent to a spatially dependent spin-orbit coupling. Higher dimensional generalizations of flat Landau levels are obtained in the Landau-like gauge. The 2D helical Dirac modes with opposite helicities and 3D Weyl modes with opposite chiralities are spatially separated along the third and fourth dimensions, respectively. Stable 2D helical Fermi surfaces and 3D chiral Fermi surfaces appear on open boundaries, respectively. The charge pumping in 4D Landau level systems shows quantized 4D quantum Hall effect.
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