On Generation Thresholds of a Chiral Laser of Circularly Polarized Radiation

We have calculated the dispersion of exciton-polariton resonance energies and linewidths, as well as the Stokes parameters of the far-field radiation of a semiconductor microcavity with a chiral photonic crystal of \({{C}_{4}}\) symmetry on the upper Bragg mirror. Lowering the symmetry of the laser generation region in such a microcavity was shown to break the degeneracy of the generation thresholds of doubly degenerate states at the \(\Gamma \) point of the Brillouin zone. This results in elliptical polarization of the laser radiation in the far field with a high degree of circular polarization. The orientation of the linearly polarized component depends on the shape of the excitation region.