Supersymmetric boundaries of one-dimensional phases of fermions beyond symmetry-protected topological states

TL;DR

This paper explores the emergence of boundary supersymmetry in one-dimensional fermionic phases beyond symmetry-protected topological states, linking Majorana modes to supercharges and calculating protected boundary supercharges from bulk invariants.

Contribution

It introduces a framework to analyze boundary supersymmetry in non-SPT fermionic phases using bulk phase invariants and Majorana edge modes.

Findings

Protected boundary supercharges are determined by bulk phase invariants.

Majorana edge modes are directly connected to real supercharges.

Boundary supersymmetry extends beyond SPT phases.

Abstract

It has recently been demonstrated that protected supersymmetry emerges on the boundaries of one-dimensional intrinsically fermionic symmetry protected trivial (SPT) phases. Here we investigate the boundary supersymmetry of one-dimensional fermionic phases beyond SPT phases. Using the connection between Majorana edge modes and real supercharges, we compute, in terms of the bulk phase invariants, the number of protected boundary supercharges.