Stueckelberg interferometry using periodically driven spin-orbit coupled Bose-Einstein condensates

TL;DR

This paper investigates how periodic modulation of Raman coupling in spin-orbit coupled Bose-Einstein condensates creates new eigenlevels and enables a tunable Stueckelberg interferometer, revealing complex spin-momentum locking and interference effects.

Contribution

It introduces a novel method to engineer a tunable Stueckelberg interferometer using periodically driven SOC BECs, demonstrating new eigenlevels and interference phenomena.

Findings

Observation of modulation-dressed eigenlevels with avoided crossings

Detection of richer spin-momentum locking effects

Implementation of a tunable Stueckelberg interferometer with interference fringes

Abstract

We study the single-particle dispersion of a spin-orbit coupled (SOC) Bose-Einstein condensate (BEC) under the periodical modulation of the Raman coupling. This modulation introduces a further coupling of the SOC dressed eigenlevels, thus creating a second generation of modulation-dressed eigenlevels. Theoretical calculations show that these modulation-dressed eigenlevels feature a pair of avoided crossings and a richer spin-momentum locking, which we observe using BEC transport measurements. Furthermore, we use the pair of avoided crossings to engineer a tunable Stueckelberg interferometer that gives interference fringes in the spin polarization of BECs.