Short-Time Enhanced Decay of Coherent Excitations in Bose-Einstein Condensates

TL;DR

This paper investigates how the decay of excitations in a Bose-Einstein Condensate (BEC) is significantly enhanced at short times when embedded in an optical lattice, with the effect increasing as the lattice depth grows.

Contribution

It demonstrates experimentally and theoretically that decay modifications observed in few-body systems also apply to many-body BEC excitations, revealing new decay dynamics.

Findings

Decay enhancement compared to Golden Rule predictions

Decay increases with lattice depth

Short-time decay modifications are applicable to many-body systems

Abstract

We study, both experimentally and theoretically, short-time modifications of the decay of excitations in a Bose-Einstein Condensate (BEC) embedded in an optical lattice. Strong enhancement of the decay is observed compared to the Golden Rule results. This enhancement of decay increases with the lattice depth. It indicates that the description of decay modifications of few-body quantum systems also holds for decay of many-body excitations of a BEC.