Evolution of Edge States and Critical Phenomena in the Rashba Superconductor with Magnetization

TL;DR

This paper investigates the evolution of Andreev bound states and their critical phenomena in Rashba superconductors with magnetization, revealing topological phase transitions and their experimental signatures.

Contribution

It uncovers two types of quantum criticality in the topological change of ABS near a quantum critical point in Rashba superconductors.

Findings

ABS can form chiral Majorana edge modes in topological phases

Quantum criticality affects the presence and energy gap of ABS near QCP

Tunneling conductance can detect these topological and critical phenomena

Abstract

We study Andreev bound states (ABS) and resulting charge transport of Rashba superconductor (RSC) where two-dimensional semiconductor (2DSM) heterostructures is sandwiched by spin-singlet s-wave superconductor and ferromagnet insulator. ABS becomes a chiral Majorana edge mode similar to that in spinless chiral p-wave pairing in topological phase (TP). We clarify that two types of quantum criticality about the topological change of ABS near a quantum critical point (QCP), whether ABS exists at QCP or not. In the former type, ABS has a energy gap and does not cross at zero energy in non-topological phase (NTP). These complex properties can be detected by tunneling conductance between normal metal / RSC junctions.