Hidden-symmetry–protected topological phases on a one-dimensional lattice
1 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences Beijing 100190, China
2 Collaborative Innovation Center of Quantum Matter - Beijing, China
Received: 7 November 2014
Accepted: 5 February 2015
We demonstrate the existence of a topologically nontrivial phase in a one-dimensional fermionic lattice system subjected to synthetic gauge fields, which is beyond the standard Altland-Zirnbauer classification of topological insulators. The topological phase can be characterized by the presence of degenerate zero-mode edge states or a quantized Berry phase of the occupied Bloch band. By analyzing symmetries of the system, we identify that the topological phase and zero-mode edge states are protected by two hidden symmetries. An extended model with hidden symmetry breaking is also studied in order to reveal the effect of hidden symmetries on the symmetry-protected topological phase.
PACS: 03.65.Vf – Phases: geometric; dynamic or topological / 71.10.Fd – Lattice fermion models (Hubbard model, etc.)
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