Polariton-polariton interaction potentials determination by pump-probe degenerate scattering in a multiple microcavity

Abstract

We study the polarization-dependent polariton-polariton interaction through its effect on a parametric scattering process in a microcavity (MC). The ratio of the anticircular interaction strength ${V}_{2}$ over its cocircular counterpart ${V}_{1}$ is involved in defining the regime in which many nonlinear processes arise in MCs, such as parametric conversion or condensation. We measure the ratio ${V}_{2}/{V}_{1}$ using a stimulated energy-degenerate parametric scattering process in a multiple MC. The sample is pumped at normal incidence, probed with a nonzero angle, and the phase-matched idler is observed at the opposite angle. The idler behavior, both in power and polarization, is compared to a Hamiltonian interaction model that takes into account the two polarization-dependent parametric scattering channels characterized by ${V}_{1}$ and ${V}_{2}$. The proposed method to measure the ratio ${V}_{2}/{V}_{1}$ is convenient and precise. The flexibility of the triple MC allows us to observe the process and measure this ratio over a large range of detunings, where we find it to be highly dependent on the detuning. These measurements complement the previous study of Vladimirova et al. [Phys. Rev. B 82, 075301 (2010)] with an original approach and for detunings that were unexplored up to now.