Spin-optronics is a new emerging research area, which combines studies of spin and optical polarisation effects in solids with the ultimate goal of creating quantum optoelectronic devices. This is an interdisciplinary research field at the crossroads of fundamental physics, optoelectronics, and nano-technology.
We present recent results on theoretical description of spin and polarization dynamics in quantum microcavities- photonic structures designed to enhance the light-matter interaction. When optically created, polaritons inherit the spin and dipole moment from the exciting light. However, from the very beginning of their life in a microcavity, polaritons start changing their spin state under effect of effective magnetic fields of different nature and scattering which makes pseudospin dynamics of exciton-polaritons rich and complex. This can be used for the creation novel spinoptronic components such as quantum beam splitters, all- optical gates and efficient sources of the entangled photon pairs. The analysis of polarization dynamics in nonlinear regime is of particular interest. We show that the interplay between the nonlinearity caused by the polariton-polariton interactions and the polarization dependence of these interactions results in a remarkable multistability of a resonantly driven polariton system, contrary to the usual optical bistability in the spin-less nonlinear case. We also consider the effects of self-organization and polarization pattern formation in regular and disordered semiconductor microcavities connected with polarization multistability.