Josephson effects in one-dimensional supersolids

TL;DR

This paper demonstrates superflow in a one-dimensional supersolid modeled by the Gross-Pitaevskii equation, revealing a Josephson effect analogous to superconductors and exploring related phenomena like persistent current.

Contribution

It provides a theoretical example of supersolidity with superflow and Josephson effects in a 1D model, extending understanding of supersolid behavior.

Findings

Superflow past an obstacle is possible in 1D supersolids.

A Josephson relation between current and phase difference is established.

Phase diagram of current versus interaction strength is presented.

Abstract

We demonstrate that superflow past an obstacle is possible in a solid phase in the one-dimensional Gross-Pitaevskii equation with a finite-range two-body interaction. The phenomenon we find is analogous to the DC Josephson effect in superconductors and we deduce the "Josephson relation" between the current and phase difference of the condensates separated by the obstacle. We also discuss persistent current and nonclassical rotational inertia in annular container with a penetrable potential barrier. The phase diagram in the plane of the current and the interaction strength is given. Our result provides a simple theoretical example of supersolidity in the presence of an obstacle.