Photon Hall Pinwheel Radiation of Angular Momentum by a Diffusing Magneto-Optical Medium.

We present a new optical effect that exchanges angular momentum between light and matter. The matter consists of an optically thick spherical, rigid agglomerate of magneto-optical scatterers placed in a homogeneous magnetic field. The light comes from an unpolarized, coherent central light source. The photon Hall effect induces a spiraling Poynting vector, both inside and outside the medium. Optical orbital angular momentum leaks out and induces a torque proportional to the injection power of the source and the photon Hall angle.