Slow propagation of photon-like polaritons generated by exciton-exciton scattering in ZnO thin filmsH. Ichida, S. Wakaiki, T. Kawase, K. Mizoguchi, D. Kim, M. Nakayama and Y. KanematsuEPJ Web of Conferences, 41 (2013) 04014DOI: https://doi.org/10.1051/epjconf/20134104014