2011/06/30 by Sumanta Tewari, Jay D. Sau, J. D. Sau +3
Materials Science · Mathematics · Physics and Astronomy · #Condensed matter physics #Graphene research and applications #Heterojunction #Magnetic field #Mathematics #Physics #Quantum #Quantum and electron transport phenomena #Quantum mechanics #Semiconductor #Superconductivity #Symmetry protected topological order #Theoretical physics #Topological Materials and Phenomena #Topological degeneracy #Topological insulator #Topological order #Topology (electrical circuits) #Zeeman effect #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.85.155302
published as Phys. Rev. B 85, 155302 (2012) · 8+ pages, 5 figures, Revised version as accepted in PRB
arxiv created 2012/03/27 · openalex publication_date 2012/04/03 · arxiv updated 2012/04/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Quantum ground states on the nontrivial side of a topological quantum critical point (TQCP) have unique properties that make them attractive candidates for quantum information applications. A recent example is provided by s-wave superconductivity on a semiconductor platform, which is tuned through a TQCP to a topological superconducting (TS) state by an external Zeeman field. Despite many attractive features of TS states, TQCPs themselves do not break any symmetries, making it impossible to distinguish the TS state from a regular superconductor in conventional bulk measurements. Here we show that for the semiconductor TQCP this problem can be overcome by tracking suitable bulk transport properties across the topological quantum critical regime itself. The universal low-energy effective theory and the scaling form of the relevant susceptibilities also provide a useful theoretical framework in which to understand the topological transitions in semiconductor heterostructures. Based on our theory, specific bulk measurements are proposed here in order to characterize the novel TQCP in semiconductor heterostructures.