The role of Mie scattering in the seeding of matter-wave superradiance

TL;DR

This paper demonstrates that Mie scattering within an atomic cloud can initiate matter-wave superradiance by creating a phase gradient and a grating, leading to coherent emission and anisotropic atomic recoil halos.

Contribution

It reveals a novel mechanism where Mie scattering triggers matter-wave superradiance, highlighting the role of collective scattering effects in ultracold atomic systems.

Findings

Mie scattering can initiate matter-wave superradiance.

The process creates anisotropic atomic recoil halos.

Interference effects produce a phase gradient and a grating.

Abstract

Matter-wave superradiance is based on the interplay between ultracold atoms coherently organized in momentum space and a backscattered wave. Here, we show that this mechanism may be triggered by Mie scattering from the atomic cloud. We show how the laser light populates the modes of the cloud, and thus imprints a phase gradient on the excited atomic dipoles. The interference with the atoms in the ground state results in a grating, that in turn generates coherent emission, contributing to the backward light wave onset. The atomic recoil 'halos' created by the scattered light exhibit a strong anisotropy, in contrast to single-atom scattering.