Zitterbewegung with spin-orbit coupled ultracold atoms in a fluctuating optical lattice

TL;DR

This paper investigates how lattice noise affects the trembling Zitterbewegung motion in ultracold atoms with spin-orbit coupling, revealing that noise prolongs the motion due to decoherence effects.

Contribution

It introduces a stochastic noise model to analyze the impact of lattice fluctuations on Zitterbewegung in spin-orbit coupled ultracold atoms, providing analytical and numerical insights.

Findings

Lattice noise significantly extends Zitterbewegung duration.

Noise induces decoherence of Rabi oscillations.

Analytical solutions are obtained for noiseless cases.

Abstract

Dynamics of non-interacting ultracold atoms with artificial spin-orbit coupling is considered. Spin-orbit coupling is created using two moving optical lattices with orthogonal polarizations. Our main goal is to study influence of lattice noise on Rabi oscillations. Special attention is paid to the phenomenon of the Zitterbewegung being trembling motion caused by Rabi transitions between states with different velocities. Phase and amplitude fluctuations of lattices are modelled by means of the two-dimensional stochastic Ornstein-Uhlenbeck process, also known as harmonic noise. In the the noiseless case the problem is solved analytically in terms of the momentum representation. It is shown that lattice noise significantly extends duration of the Zitterbewegung as compared to the noiseless case. This effect originates from noise-induced decoherence of Rabi oscillations.