Conical Refraction: Forgotten Phenomenon or Novel Tool for Phase Preservation of Orbital Angular Momentum of Light Propagating Through Scattering Media

Conical refraction (CR) is a phenomenon observed when light is transformed into a hollow slanted cone propagating along an optical axis of a biaxial crystal and emerges as a cylinder of light behind the exit facet of the crystal [1]. The beam shape can display different patterns depending on the propagation length of the focused light (Fig. 1a). To study the CR effect and explore the propagation of the vortex-structured laser beam-shaped light carrying orbital angular momentum (OAM) through a scattering medium, we have developed a Mach-Zehnder interferometer (Fig. 1 b).