English

Detecting Topological Superconductivity via Berry Curvature Effects in Spectral Functions

Superconductivity 2025-02-17 v3

Abstract

Experimental efforts on topological superconductivity (TSC) have primarily focused on the detection of Majorana boundary modes, while the bulk properties of TSC - particularly in two dimensions (2D) - remain relatively underexplored. In this work, we theoretically propose a distinctive signature in the spectral function away from the boundaries, capable of detecting 2D chiral p-wave TSC induced in a Rashba spin-orbit-coupled (SOC) heterostructure. This signature can be probed experimentally through angle-resolved photoemission spectroscopy or momentum- and energy-resolved tunneling spectroscopy under a weak magnetic field B. We show that within the topological phase, the spectral intensity of the lowest superconducting band at small momenta k~0 brightens (darkens) linearly with increasing B, whereas it darkens (brightens) in the trivial phase when the Rashba system is electron- (hole-) doped. This sharp contrast arises from the phase-space Berry curvature (BC) of Bogoliubov quasiparticles, a novel quantum geometric property that generalizes the conventional momentum-space BC. The effect of this phase-space BC can also be detected by the differential conductance away from the boundaries. Our falsifiable prediction provides an experimental avenue for detecting Rashba-induced chiral p-wave TSC without relying on Majorana mode detection, addressing a key challenge in the realization of 2D TSC.

Keywords

Cite

@article{arxiv.2311.02165,
  title  = {Detecting Topological Superconductivity via Berry Curvature Effects in Spectral Functions},
  author = {Yunxiang Liao and Yi-Ting Hsu},
  journal= {arXiv preprint arXiv:2311.02165},
  year   = {2025}
}

Comments

13 pages, 4 figures