Dynamical preparation of stripe states in spin-orbit coupled gases

TL;DR

This paper demonstrates a method to coherently prepare stripe phases in spin-orbit coupled Bose-Einstein condensates by modulating spin-dependent collisions through Raman coupling, enabling control over quantum phase transitions.

Contribution

It introduces a dressed-basis approach to effectively simulate tunable spin-changing collisions, facilitating the dynamical creation of stripe states in spin-orbit coupled gases.

Findings

Effective Hamiltonian equivalent to a tunable spinor gas.

Proposed protocol for driving condensates into stripe phases.

Robustness of the method against experimental imperfections.

Abstract

In spinor Bose-Einstein condensates, spin-changing collisions are a remarkable proxy to coherently realize macroscopic many-body quantum states. These processes have been, e.g., exploited to generate entanglement, to study dynamical quantum phase transitions, and proposed for realizing nematic phases in atomic condensates. In the same systems dressed by Raman beams, the coupling between spin and momentum induces a spin dependence in the scattering processes taking place in the gas. Here we show that, at weak couplings, such modulation of the collisions leads to an effective Hamiltonian which is equivalent to the one of an artificial spinor gas with spin-changing collisions that are tunable with the Raman intensity. By exploiting this dressed-basis description, we propose a robust protocol to coherently drive the spin-orbit coupled condensate into the ferromagnetic stripe phase via crossing a quantum phase transition of the effective low-energy model in an excited-state.