The Photon Hall Pinwheel, Radiation of Angular Momentum by a Diffusing Magneto-optical Medium

TL;DR

This paper demonstrates that a magneto-optical medium can generate and emit electromagnetic angular momentum through the Photon Hall Effect, resulting in a torque proportional to the source power and magnetic field, revealing a new optical phenomenon.

Contribution

It introduces a novel class of optical phenomena where diffusive magneto-transport produces angular momentum and torque from a diffusing magneto-optical medium.

Findings

Electromagnetic angular momentum leaks out of the medium.

A torque proportional to source power and photon Hall angle is induced.

The effect occurs inside and outside the magneto-optical agglomerate.

Abstract

We consider an optically thick spherical agglomerate of magneto-optical scatterers with a central isotropic, unpolarized light source, placed in a homogeneous magnetic field. The Photon Hall Effect induces a rotating Poynting vector, both inside and outside the medium. We show that electromagnetic (orbital) angular momentum leaks out and induces a torque proportional to the injection power of the source and the photon Hall angle. This effect represents a novel class of optical phenomena, generating angular momentum from diffusive magneto-transport.