Hidden-symmetry–protected topological phases on a one-dimensional lattice. (25th February 2015)

• Record Type: Journal Article
• Authors: Li, Linhu; Chen, Shu
• Is Part Of: Europhysics letters. Volume 109:Number 4(2015:Feb.)
• Publication Date: 2015-02-25
• Subjects: 03.65.Vf -- 71.10.Fd; Physics -- Periodicals; Electronic journals; 530.05
• DOI: 10.1209/0295-5075/109/40006
• Languages: English
• ISSNs: 0295-5075

Abstract

Abstract: 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.