2012/07/03 by Zohar Ringel, Ehud Altman
Materials Science · Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Charge (physics) #Combinatorics #Condensed matter physics #Electronic and Structural Properties of Oxides #Gapless playback #Geometry #Mathematics #Phase (matter) #Phase diagram #Phase transition #Physics #Quantum #Quantum mechanics #Symmetry (geometry) #Topological Materials and Phenomena #Topological insulator #Topological order #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.87.035115
arxiv created 2012/07/03 · openalex publication_date 2013/01/11 · arxiv updated 2015/06/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
When time-reversal symmetry is present there is a sharp distinction between topological and trivial band insulators which ensures that, as parameters are varied, these phases are separated by a phase transition at which the bulk gap closes. Surprisingly we find that even in the absence of time-reversal symmetry, gapless regions originating from the phase boundaries persist. Moreover, the critical line generically opens up to enclose Chern insulating phases that are thin but of finite extent in the phase diagram. We explain the topological origin of this effect in terms of quantized charge pumping, showing in particular that it is robust to the effect of disorder and interactions.