Honing in on a topological zero-bias conductance peak

TL;DR

This paper proposes experimental methods to distinguish topological Majorana zero-bias conductance peaks from trivial ones by analyzing local density of states and magnetization density oscillations.

Contribution

It introduces a novel approach using local density of states and magnetization density to differentiate topological from trivial zero-bias conductance peaks.

Findings

Trivial peaks show oscillations in local density of states and magnetization density.

Topological peaks lack these oscillations, providing a clear distinguishing feature.

The methods offer practical experimental probes for identifying Majorana states.

Abstract

A popular signature of Majorana bound states in topological superconductors is the zero-energy conductance peak with a height of $2e^2/h$. However, a similar zero energy conductance peak with almost the same height can also arise due to non-topological reasons. Here we show that these trivial and topological zero energy conductance peaks can be distinguished via the zero energy local density of states and local magnetization density of states. We find that the zero-energy local density of states exhibits oscillations with a finite period for a trivial zero-bias conductance peak. In contrast, these oscillations disappear for the topological zero-bias conductance peak. On the other hand, zero energy local magnetization density of states shows a periodic oscillation for trivial zero-bias conductance peak, while for topological ZBCP, they vanish. Our results suggest that zero-energy local density of states and local magnetization density of states can be used as an experimental probe to distinguish trivial zero energy conductance peak from topological zero energy conductance peak.