2013/10/31 by Stephan Rachel · 1 citation
Materials Science · Physics and Astronomy · #Chemical and Physical Properties of Materials #Invariant (physics) #Phase transition #Quantum and electron transport phenomena #Quantum phase transition #Quantum phases #Symmetry protected topological order #Topological Materials and Phenomena #Topological insulator #Topological order #Topology (electrical circuits) #cond-mat.str-el
paper · pdf · doi:10.1088/0953-8984/28/40/405502
published as J. Phys.: Condens. Matter 28, 405502 (2016) · v3: 15 pages, 5 figures; refs. added - final version
arxiv created 2016/08/12 · openalex publication_date 2016/08/17 · arxiv updated 2016/08/18 · openalex created_date 2016/08/23 · openalex updated_date 2026/08/05
We consider two-dimensional Chern insulators and time-reversal invariant topological insulators and discuss the effect of perturbations breaking either particle-number conservation or time-reversal symmetry. The appearance of trivial mass terms is expected to cause quantum phase transitions into trivial phases when such a perturbation overweighs the topological term. These phase transitions are usually associated with a bulk-gap closing. In contrast, the chiral Chern insulator is unaffected by particle-number breaking perturbations. Moreover, the [Formula: see text] topological insulator undergoes phase transitions into topologically trivial phases without bulk-gap closing in the presence of any of such perturbations. In certain cases, these phase transitions can be circumvented and the protection restored by another U(1) symmetry, e.g. due to spin conservation. These findings are discussed in the context of interacting topological insulators.