Abstract:
A left-handed chiral sculptured thin film (STF) that reflects strongly at the wavelength of the circular Bragg resonance
tends to partially convert the handedness of incident LCP (left-circularly-polarized) light to RCP (right-circularly-
polarized). We show that the cross-polarized component of the reflected RCP beam can be eliminated by
interference with an additional RCP beam that is reflected at the interface of an isotropic cover and an AR (antireflecting)
layer. For best results the refractive index and thickness of the AR layer need to accommodate a phase change
on reflection that occurs at the chiral film. Effective suppression of the reflectances RRR, RRL, RLR and the transmittances
TRL, TLR can be achieved by sandwiching the chiral reflector between such amplitude and phase-matched AR coatings.
Co-polarized chiral reflectors of this type may form efficient handed optical resonators. For LCP light the optical
properties of such a handed resonator are formally the same as the properties of the isotropic passive or active Fabry–
Perot resonators, but the handed resonator is transparent to RCP light.
