Voltage control of the spin-dependent interaction constants of Dipolaritons and its application to Optical Parametric Oscillator

Abstract

Dipolariton is a voltage controlled mixture of direct and indirect excitons in asymmetric double quantum wells coupled by resonant carrier tunneling, and a microcavity photon. We calculate the voltage dependence of the spin-singlet and spin-triplet interaction parameters $α_{1}$ and $α_{2}$. Both parameters can reach values one order of magnitude larger than that of exciton-polaritons thanks to the strong interaction between indirect excitons. We show that the variation of the indirect exciton fraction of the dipolaritons induces a changes of sign of $α_{2}$ increasing voltage: the interaction passes from attractive to repulsive. For large enough voltage $α_{2}$ becomes larger than $α_{1}$ which in principle can lead to the formation of a circularly polarised dipolariton condensate. We propose an application of the $α_{2}$ dependence to a voltage-controlled dipolaritonic optical parametric oscillator. The change of sign of $α_{2}$ allows an on-site control of the linear polarization degree of the optical signal and its on-demand inversion.