Transmission-mode geometric-phase signatures of circular Bragg phenomenon

Abstract

A dielectric structurally chiral medium (DSCM) exhibits the circular Bragg phenomenon, whereby circular-polarization-state selective reflection occurs in a specific spectral regime that depends on the direction of propagation of the incident plane wave. Theoretical analysis shows that the geometric-phase spectrum of the plane wave transmitted through a DSCM slab contains a signature of the circular Bragg phenomenon, provided that the incident plane wave is not right-circularly polarized, regardless of the structural handedness of the DSCM. As the number of structural periods in the DSCM slab increases with the structural period fixed, the spectrum of the transmission-mode geometric phase evolves but without an easily discernible pattern. A reversal of structural handedness affects but does not lead to a simple change in the transmission-mode geometric phase.