Solitonlike Propagation of Exciton-Polariton Pulses Supported by Biexciton Two-Photon Dispersion

Abstract
We present a new scheme of distortion free propagation of exciton-polariton pulses in the low-intensity region. In this scheme, the anomalous nonlinear dispersion associated with the biexciton two-photon transition compensates the group velocity dispersion to maintain the pulse duration. We demonstrate the distortion free propagation of polariton pulses in CuCl. We compare the observed pulse profiles with the calculated profiles using the frequency domain wave equation, where the lowest-order coherent nonlinearity is taken into account. We obtain good agreement between the experiment and the calculation.