Soliton-like propagation in biexciton two-photon resonant region

Soliton-like pulse propagation in the exciton resonant region is the issue of current interest because of their importance in the ultrafast optical switching devices. Although several types of polariton solitons at exciton resonance have been theoretically proposed, experimental studies for soliton-like propagation in such region have not been fully explored. Recently, we proposed a new scheme of soliton-like propagation supported by biexciton two-photon dispersion, and demonstrated a preliminary indication of our scheme using biexciton two-photon resonance (TPR) in CuCl. In the present study, we perform sub-ps pulse propagation experiments under several conditions using biexciton TPR in CuCl. We compare the results with the calculated results using the frequency domain wave equation. We obtain good agreement between them, and confirm soliton-like propagation supported by biexciton two-photon dispersion.