Plateau regions for zero-bias peaks within 5% of the quantized conductance value $2e^2/h$

TL;DR

This paper reports the observation of zero-bias peaks in InAs-Al nanowires that remain close to the quantized conductance value of 2e^2/h over a range of parameters, supporting the existence of Majorana zero modes.

Contribution

It demonstrates large zero-bias peaks with conductance plateaus within 5% of 2e^2/h in hybrid nanowires, advancing the experimental evidence for Majorana zero modes.

Findings

Zero-bias peaks close to 2e^2/h observed

Identification of plateau regions in phase space

Robustness of conductance against parameter tuning

Abstract

Probing an isolated Majorana zero mode is predicted to reveal a tunneling conductance quantized at $2e^2/h$ at zero temperature. Experimentally, a zero-bias peak (ZBP) is expected and its height should remain robust against relevant parameter tuning, forming a quantized plateau. Here, we report the observation of large ZBPs in a thin InAs-Al hybrid nanowire device. The ZBP height can stick close to $2e^2/h$, mostly within $5\%$ tolerance, by sweeping gate voltages and magnetic field. We further map out the phase diagram and identify two plateau regions in the phase space. Despite the presence of disorder and quantum dots, our result constitutes a step forward towards establishing Majorana zero modes.