Recent studies of two-photon excitation of exciton-polaritons in microcavities have considered the possibility of an allowed absorption process into the 2p-state of the excitons which participate in the polariton effect. Here we report time-resolved measurements of two-photon excitation directly into the lower polariton states invoking the 1s state of the excitons. Although this process is forbidden by symmetry for light at normal incidence, it is allowed at non-zero angle of incidence due to state mixing.
@article{arxiv.1608.05504,
title = {Time-resolved two-photon excitation of long-lifetime polaritons},
author = {Chitra Gautham and Mark Steger and David Snoke and Ken West and Loren Pfeiffer},
journal= {arXiv preprint arXiv:1608.05504},
year = {2016}
}