Vortex droplets and lattice patterns in two-dimensional traps: A photonic spin–orbit-coupling perspective

Abstract

In the context of the mean-field exciton-polariton (EP) theory with balanced loss and pump, we investigate the formation of lattice structures built of individual vortex-antivortex (VAV) bound states under the action of the two-dimensional harmonic-oscillator (HO) potential trap and effective spin–orbit coupling (SOC), produced by the TE-TM splitting in the polariton system. The number of VAV elements (“pixels”) building the structures grow with the increase of self- and cross-interaction coefficients. Depending upon their values and the trapping frequency, stable ring-shaped, circular, square-shaped, rectangular, pentagonal, hexagonal, and triangular patterns are produced, with the central site left vacant or occupied in the lattice patterns of different types. The results suggest the experimental creation of the new patterns and their possible use for the design of integrated circuits in EP setups, controlled by the strengths of the TE-TM splitting, nonlinearity, and HO trap.