Determination of the Superconductor-Insulator Phase Diagram for One-Dimensional Wires

TL;DR

This study maps the superconductor-insulator phase diagram for MoGe nanowires, confirming the critical resistance aligns with theoretical predictions and revealing weak Coulomb blockade effects in insulating wires.

Contribution

First experimental determination of the superconductor-insulator phase boundary in quasi-one-dimensional wires confirming theoretical models.

Findings

Critical resistance matches R_Q = h/4e^2

Insulating wires show weak Coulomb blockade behavior

Phase diagram consistent with Chakravarty-Schmid-Bulgadaev boundary

Abstract

We establish the superconductor-insulator phase diagram for quasi-one dimensional wires by measuring a large set of MoGe nanowires. This diagram is consistent with the Chakravarty-Schmid-Bulgadaev phase boundary, namely with the critical resistance being equal to R_Q = h/4e^2. We find that transport properties of insulating nanowires exhibit a weak Coulomb blockade behavior.