Anharmonicity Induced Supersolidity In Spin-Orbit Coupled Bose-Einstein Condensates

TL;DR

This paper demonstrates that combining anharmonic trapping potentials with spin-orbit coupling in ultracold Bose gases can induce supersolidity, revealing topological properties like skyrmion lattices.

Contribution

It introduces a new method to realize supersolids using anharmonic traps and spin-orbit coupling in Bose-Einstein condensates, supported by numerical simulations.

Findings

Supersolid states emerge in spin-orbit coupled Bose gases in anharmonic traps.

A skyrmion-anti-skyrmion lattice is associated with the supersolid phase.

Topological properties are linked to the supersolid state in this system.

Abstract

Supersolid, a fascinating quantum state of matter, features novel phenomena such as the non-classical rotational inertia and transport anomalies. It is a long standing issue of the coexistence of superfluidity and broken translational symmetry in condensed matter physics. By recent experimental advances to create tunable synthetic spin-orbit coupling in ultracold gases, such highly controllable atomic systems would provide new possibilities to access supersolidity with no counterpart in solids. Here we report that the combination of anharmonicity of trapping potential and spin-orbit coupling will provide a new paradigm to achieve supersolids. By means of imaginary time evolution of the Gross-Pitaevskii equation, we demonstrate that a supersolid state can be found when considering a trapped Rashba-type spin-orbit coupled bosonic atoms loaded in a one-dimensional optical lattice. Furthermore, a skyrmion-anti-skyrmion lattice is associated with the appearance of such supersoildity, indicating the topological nontrivial properties of our proposed supersolids.