Waveguiding driven by the Pancharatnam-Berry phase

We theoretically and numerically investigate the properties of waveguides based on Pancharatnam-Berry phase, obtained by a longitudinally periodic rotation optic axis in transversely twisted birefringent medium. In this paper we study case where period longitudinal modulation is chosen so that net accumulation geometric phase propagation occurs. First, interplay between different contributions to optical potential addressed. Second, continuous evolution polarization structure quasimodes observed numerical simulations. explain it combination plane-wave-based models gauge transformations. discover that, beyond oscillations, quasimode also varies through its cross section. The analogies with respect charged particles moving magnetic field are outlined.