Circularly polarized lasing in chiral modulated semiconductor   microcavity with GaAs quantum wells
  We report the elliptically, close to circularly polarized lasing at $\hbar\omega = 1.473$ and 1.522 eV from an AlAs/AlGaAs Bragg microcavity with 12 GaAs quantum wells in the active region and chiral-etched upper distributed Bragg refractor under optical pump at room temperature. The advantage of using the chiral photonic crystal with a large contrast of dielectric permittivities is its giant optical activity, allowing to fabricate a very thin half-wave plate, with a thickness of the order of the emitted light wavelength, and to realize the monolithic control of circular polarization. 
A. A. Demenev, V. D. Kulakovskii, C. Schneider, S. Brodbeck, M. Kamp,   S. H\"ofling, S. V. Lobanov, T. Weiss, N. A. Gippius...
physics.optics