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

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.