Electromagnetic confinement via spin-orbit interaction in anisotropic dielectrics

Abstract

We investigate electromagnetic propagation in uniaxial dielectrics with a transversely varying orientation of the optic axis, the latter staying orthogonal everywhere to the propagation direction. In such a geometry, the field experiences no refractive index gradients, yet it acquires a transversely-modulated Pancharatnam-Berry phase, that is, a geometric phase originating from a spin-orbit interaction. We show that the periodic evolution of the geometric phase versus propagation gives rise to a longitudinally-invariant effective potential. In certain configurations, this geometric phase can provide transverse confinement and waveguiding. The theoretical findings are tested and validated against numerical simulations of the complete Maxwell's equations. Our results introduce and illustrate the role of geometric phases on electromagnetic propagation over distances well exceeding the diffraction length, paving the way to a whole new family of guided waves and waveguides which do not rely on refractive index tailoring.

16 pages, 4 figures

References in corpus (5)

• Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media
• Photonic Analogue of Two-dimensional Topological Insulators and Helical One-Way Edge Transport in Bi-Anisotropic Metamaterials
• Coriolis Effect in Optics: Unified Geometric Phase and Spin-Hall Effect
• Pancharatnam-Berry phase optical elements for wavefront shaping in the visible domain: switchable helical modes generation
• Non-Abelian evolution of electromagnetic waves in a weakly anisotropic inhomogeneous medium

Cited by in corpus (2)

• Interplay between diffraction and the Pancharatnam-Berry phase in inhomogeneously twisted anisotropic media
• Spin-orbit interactions in optically active materials