We study light scattering of single atoms in free space and discuss the results in terms of atom-photon entanglement and which-way information. Using ultracold atoms released from an optical lattice, we realize a Gedanken experiment which interferes single photons scattering off of Heisenberg uncertainty-limited wavepackets. We unify the free-space and trapped-atom pictures by measuring the light scattered during wavepacket expansion and show the coherence properties of the scattered light is independent of the presence of the trap. Our experiment demonstrates the potential of using atomic Mott insulators to create single-atom wavepackets for fundamental studies.
@article{arxiv.2410.19671,
title = {Coherent and incoherent light scattering by single-atom wavepackets},
author = {Vitaly Fedoseev and Hanzhen Lin and Yu-Kun Lu and Yoo Kyung Lee and Jiahao Lyu and Wolfgang Ketterle},
journal= {arXiv preprint arXiv:2410.19671},
year = {2024}
}