Polariton polarization rectifier

Spontaneous symmetry breaking in persistent currents of spinor polaritons

We predict the spontaneous symmetry breaking in a spinor Bose–Einstein condensate of exciton-polaritons (polaritons) caused by the coupling of its spin and orbital degrees of freedom. We study a polariton condensate trapped in a ring-shaped effective potential with a broken rotational symmetry. We propose a realistic scheme of generating controllable spinor azimuthal persistent currents of polaritons in the trap under the continuous wave optical pump. We propose a new type of half-quantum circulating states in a spinor system characterized by azimuthal currents in both circular polarizations and a vortex in only one of the polarizations. The spontaneous symmetry breaking in the spinor polariton condensate that consists in the switching from co-winding to opposite-winding currents in opposite spin states is revealed. It is characterized by the change of the average orbital angular momentum of the condensate from zero to non-zero values. The radial displacement of the pump spot and the polarization of the pump act as the control parameters. The considered system exhibits a fundamental similarity to a superconducting flux qubit, which makes it highly promising for applications in quantum computing.

Polygonal patterns of confined light

We propose a technique for the generation of polygonal optical patterns in real space using a combined effect of the spin-orbit interaction and confinement of light in the plane of a dielectric optical microcavity. The spin-orbit interaction emerging from the splitting in transverse electric (TE) and transverse magnetic (TM) optical modes of the microcavity gives rise to oscillations in space of propagating macroscopic wave packets of polarized photons. Confined in a harmonic potential, the latter follow closed trajectories of a polygonal form. We demonstrate the possibility of excitation by a continuous wave resonant optical pumping of polygonal optical patterns with a controllable (both even and odd) number of vertices.

Extinction ratio and image accuracy of relayed-microgrid polarimetric imaging systems: theory and experiment

Herein we propose a polarimetric imaging system that uses a microgrid polarizer placed on the conjugate point of two telecentric optical paths, matching large polarizers with small sensors and thus effectively decreasing optical crosstalk and increasing imaging accuracy. We define a new parameter used to construct the high-precision polarization vector transfer model under crosstalk. Using the equivalent surface of the detector, we establish the relationship between focal shift and crosstalk ratio and obtain a multi-physical coupling mathematical model that accounts for the crosstalk ratio, extinction ratio, sensor error, target vector, and imaging accuracy of the system. The relayed-microgrid polarimetric imaging system is anticipated to be able to help identify objects of interest for remote sensing and military applications.