Interaction-driven losses for atoms in a dark-state lattice

TL;DR

This paper estimates collisional loss rates of ultracold bosons in dark-state optical lattices with subwavelength features, finding low loss rates that support their potential use in quantum simulations.

Contribution

It introduces a method to estimate collisional losses in dark-state lattices using Fermi's Golden Rule, highlighting conditions for minimal losses in a $ ext{Lambda}$ system.

Findings

Loss rates are influenced by laser strength and detuning.

Maximum losses occur with blue-detuned two-photon transitions.

Predicted loss rates are sufficiently low for practical applications.

Abstract

In this work we estimate the collisional loss rate of ultracold bosons in the optical potential featuring subwavelength-width peaks. This is established by using $\Lambda$ arrangement of three atomic states coupled (almost) resonantly by lasers. Using Fermi's Golden Rule, we find that the loss rate is influenced by the overall strength of the lasers, with the largest losses occurring when the two-photon transition is blue-detuned from the excited state of the $\Lambda$ system. Overall, the predicted loss rates are low, which may allow the use of ultracold bosons in the construction of dark-state potentials in the $\Lambda$-type many-level system.