Fingerprints of bosonic symmetry protected topological state in a quantum point contact
arXiv:1610.01236 · doi:10.1103/PhysRevLett.118.216803
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.
16 pages, 5 figures
References in corpus (13)
- Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
- Quantum Spin Hall Insulator State in HgTe Quantum Wells
- Biased bilayer graphene: semiconductor with a gap tunable by electric field effect
- Asymmetry gap in the electronic band structure of bilayer graphene
- The electronic properties of bilayer graphene
- Quantum Spin Hall Effect in Inverted Type II Semiconductors
- Kondo effect in the helical edge liquid of the quantum spin Hall state
- Evidence for a Spin Phase Transition at ν=0 in Bilayer Graphene
- Corner Junction as a Probe of Helical Edge States
- Tunneling between edge states in a quantum spin Hall system
- Quantum Phase Transitions Between Bosonic Symmetry Protected Topological States Without Sign Problem: Nonlinear Sigma Model with a Topological Term
- Topological edge Mott insulating state in two dimensions at finite temperatures -bulk and edge analysis-
- Bilayer Graphene as a platform for Bosonic Symmetry Protected Topological States