title: Enhanced optical activity and circular dichroism in twisted photonic crystal fiber.
abstract: We demonstrate experimentally and theoretically that the core-guided mode in helically twisted photonic crystal fiber exhibits resonantly enhanced optical activity and circular dichroism in the vicinity of anti-crossings with leaky orbital angular momentum (OAM) modes in the cladding. This arises because the anti-crossings for left and right circularly polarized core modes occur at slightly different wavelengths.
authors.forename: G K L
authors.initials: GK
authors.lastname: Wong
authors.forename: X M
authors.initials: XM
authors.lastname: Xi
authors.forename: M H
authors.initials: MH
authors.lastname: Frosz
authors.forename: P St J
authors.initials: PS
authors.lastname: Russell