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

Romain Bachelard (1) , Helmar Bender (1) , Philippe W. Courteille (1) , Nicola Piovella (2) , Christian Stehle (3) , Claus Zimmermann (3) , Sebastian Slama (3)

1 IFSC-USP - Instituto de Física de São Carlos
2 UNIMI - Università degli Studi di Milano = University of Milan
3 Physikalisches Institut [Tübingen]

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 that the system evolves into a superposition of states, where the scattering process imprints a {\it phase grating} on the atomic dipoles. This grating generates coherent emission even when there is at most one excited atom in the system at a time, 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.

Domaines: Physique Atomique [physics.atom-ph]; Optique [physics.optics]

Romain Bachelard, Helmar Bender, Philippe W. Courteille, Nicola Piovella, Christian Stehle, et al.. The role of Mie scattering in the seeding of matter-wave superradiance. 2012. ⟨hal-00702284v1⟩