Abstract:

Large ensembles of laser-cooled atoms interacting via photon-mediated interactions are powerful platforms for quantum simulation and sensing. In this talk, I will present a cavity-QED system with matter waves coupled to a high-finesse cavity. In this system, by coupling external states to atomic internal states, we successfully generated entanglement between atomic momentum states and realized the first entangled matter-wave interferometer [1]. Without coupling the momentum states to the spin states, we also realized momentum-exchange interactions [2] and collective XYZ models [3] in a Bragg interferometer, which leads to a collective recoil mechanism that effectively binds wave packets together to suppress Doppler dephasing, and the first demonstration of two-axis counter-twisting dynamics with momentum states. I will conclude the talk with a recent experiment where we realize three and four-body interaction between momentum states [4], paving the way for quantum simulation beyond pair-wise interactions and generation of exotic entangled states.

[1] G. P. Greve*, C. Luo*, B. Wu, J. K. Thompson, Nature 610, 472-477 (2022)

[2] C. Luo, H. Zhang, V. P. W. Koh, J. D. Wilson, A. Chu, M. J. Holland, A. M. Rey, J. K. Thompson, Science 384, 551-556 (2024)

[3] C. Luo*, H. Zhang*, A. Chu, C. Maruko, A. M. Rey, J. K. Thompson, arXiv preprint, arXiv: 2402.19429 (2024)

[4] C. Luo, H. Zhang, A. Chu, C. Maruko, A. M. Rey, J. K. Thompson, arXiv preprint, arXiv:2410.12132 (2024)

Short Bio:

Chengyi Luo received his PhD from JILA/University of Colorado, Boulder supervised by James K. Thompson. He is currently an AWS Quantum postdoctoral scholar at the California Institute of Technology working with Andrei Faraon. His research interest involves different cavity-QED systems, from matter waves in a Fabry-Perot cavity to rare-earth ions in nano-photonic and microwave resonators.