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 V2 over its cocircular counterpart V1 is involved in defining the regime in which many nonlinear processes arise in MCs, such as parametric conversion or condensation. We measure the ratio V2/V1 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 V1 and V2. The proposed method to measure the ratio V2/V1 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 [Phys. Rev. B 82, 075301 (2010)PRBMDO1098-012110.1103/PhysRevB.82.075301] with an original approach and for detunings that were unexplored up to now.