Collective Feshbach scattering of a superfluid droplet from a mesoscopic two-component Bose-Einstein condensate

TL;DR

This paper investigates how a superfluid droplet scatters off a mesoscopic two-component Bose-Einstein condensate, revealing controllable resonant transmission properties influenced by optical coupling, with potential applications in quantum control.

Contribution

It introduces a mean-field and numerical analysis of Feshbach-like resonant scattering in a two-component BEC, demonstrating optical control over transmission.

Findings

Resonant scattering phase shifts match numerical simulations.

Transmission can be tuned from 0 to 100% via optical fields.

Analytical approximations effectively describe the scattering process.

Abstract

We examine the collective scattering of a superfluid droplet impinging on a mesoscopic Bose-Einstein condensate (BEC) as a target. The BEC consists of an atomic gas with two internal electronic states, each of which is trapped by a finite-depth external potential. An off-resonant optical laser field provides a localized coupling between the BEC components in the trapping region. This mesoscopic scenario matches the microscopic setup for Feshbach scattering of two particles, when a bound state of one sub-manifold is embedded in the scattering continuum of the other sub-manifold. Within the mean-field picture, we obtain resonant scattering phase shifts from a linear response theory in agreement with an exact numerical solution of the real time scattering process and simple analytical approximations thereof. We find an energy-dependent transmission coefficient that is controllable via the optical field between 0 and 100%.