Parity time symmetry in two dimensional chiral optical lattice, via positive and negative refraction

Abstract

The parity time symmetry and positive/negative refraction is investigated in chiral optical lattice. Significant parity time symmetry is reported in five level chiral optical lattice which satisfied the conditions Re(nr(±)(x,y))=Re(nr∗(±)(−x,−y) and Im(nr(±)(x,y))=−Im(nr∗(±)(−x,−y) for left and right circularly polarized beams. The related group indices, phase shifts and divergent angle are also satisfied the parity time symmetry conditions ng(±)(x,y))=ng∗(±)(−x,−y), ϕ(±)(x,y))=ϕ∗(±)(−x,−y) and θd,g(x,y)=θd,g∗(−x,−y) for left and right circularly polarized beams. Maximum negative group index is calculated to −25000. The maximum phase and group divergent angles are reported to 0.001 radian and −0.9 radian. The phase shifts in LCP and RCP beams are investigated to ±0.004 radian at a length L=10λ. The modified results have potential application in nanotechnology.