Supersolid with nontrivial topological spin textures in spin-orbit-coupled Bose gases

TL;DR

This paper proposes a method to realize a supersolid phase with topologically nontrivial spin textures in spin-orbit-coupled Bose gases, detectable through momentum distribution measurements in ultracold atomic experiments.

Contribution

It demonstrates that a supersolid phase with topological spin textures can be achieved in spin-orbit-coupled Bose gases with contact interactions, expanding the understanding of supersolid states.

Findings

Supersolid phase characterized by coexisting solid and superfluid orders.

Topologically nontrivial spin textures accompany the supersolid phase.

Momentum distribution peaks indicate the phase, observable via time-of-flight experiments.

Abstract

Supersolid is a long-sought exotic phase of matter, which is characterized by the coexistence of a diagonal long-range order of solid and an off-diagonal long-range order of superfluid. Possible candidates to realize such a phase have been previously considered, including hard-core bosons with long-range interaction and soft-core bosons. Here we demonstrate that an ultracold atomic condensate of hard-core bosons with contact interaction can establish a supersolid phase when simultaneously subjected to spin-orbit coupling and a spin-dependent periodic potential. This supersolid phase is accompanied by topologically nontrivial spin textures, and is signaled by the separation of momentum distribution peaks, which can be detected via time-of-flight measurements. We also discuss possibilities to produce and observe the supersolid phase for realistic experimental situations.