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arXiv · 1610.01236

Fingerprints of bosonic symmetry protected topological state in a quantum point contact

Rui-Xing Zhang·Chao-Xing Liu
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Abstract

In this work, we study the transport through a quantum point contact for bosonic helical liquid that exists at the edge of a bilayer graphene under a strong magnetic field. We identify "smoking gun" transport signatures to distinguish bosonic symmetry protected topological (BSPT) state from fermionic two-channel quantum spin Hall (QSH) state in this system. In particular, a novel charge insulator/spin conductor phase is found for BSPT state, while either charge insulator/spin insulator or charge conductor/spin conductor phase is expected for the two-channel QSH state. Consequently, a simple transport measurement will reveal the fingerprint of bosonic topological physics in bilayer graphene systems.

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Rui-Xing Zhang, Chao-Xing Liu. 2017-07-07. Fingerprints of bosonic symmetry protected topological state in a quantum point contact. https://doi.org/10.1103/physrevlett.118.216803

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