Terahertz isotropic photonic magnetoresistance

Abstract

Ferromagnetic particle collections typically possess anisotropic terahertz (THz) transmission properties that are sensitive to the orientation of an applied external magnetic field. Here, we show that the particle surface morphology can have a large and dominant effect on the magnetic field orientation dependence of the THz transmission. In particular, the THz transmission through highly porous ferromagnetic Ni particles shows isotropic dependence on the external magnetic field orientation. This isotropic magnetic phenomenon suggests the possibility of innovative photonic materials with tailored magnetic properties.