title: Higher order Pancharatnam-Berry phase and the angular momentum of light.
abstract: The first experimental demonstration of a new Pancharatnam-Berry phase for light beams with spatially inhomogeneous, or vector, states of polarization referred to as the higher-order Pancharatnam-Berry phase is presented. This new geometric phase is proportional to light's total angular momentum, a sum of spin and higher dimensional orbital angular momentum, sharply contrasting the well-known Pancharatnam-Berry phase associated with the plane wave state of polarization of a spatially homogeneous light beam. The higher-order Pancharatnam-Berry phase is directly related to the rotational symmetry of a vortex-bearing electromagnetic field, associated with the rotational frequency shift of a light beam, and has implications in quantum information science as well as other physical systems such as electron vortex beams.
authors.affiliation: The City College of New York of The City University of New York, 160 Convent Avenue New York, New York 10031, USA. giomilione@gmail.com
authors.forename: Giovanni
authors.initials: G
authors.lastname: Milione
authors.forename: S
authors.initials: S
authors.lastname: Evans
authors.forename: D A
authors.initials: DA
authors.lastname: Nolan
authors.forename: R R
authors.initials: RR
authors.lastname: Alfano