The optical responses of solids are typically understood to be local in space. Whether locality holds for the optical response of a macroscopic quantum system has, however, been largely unexplored. Here, we use multidimensional coherent spectroscopy at the optical diffraction limit to demonstrate nonlocal optical nonlinearities in a semiconductor microcavity. These nonlocal optical responses are both coherent and quantum in nature, deriving from the macroscopic length scale of confined exciton-polariton wavefunctions.
@article{arxiv.2504.13830,
title = {Nonlocal Coherent Optical Nonlinearities of a Macroscopic Quantum System},
author = {Albert Liu and Eric W. Martin and Jiaqi Hu and Zhaorong Wang and Hui Deng and Steven T. Cundiff},
journal= {arXiv preprint arXiv:2504.13830},
year = {2025}
}