Verdet's Constant

(named after the French mathematician M. Verdet; 1824-66), a quantity that characterizes the magnetic rotation of the plane of polarization in a substance. A substance placed in a magnetic field turns the plane of polarization of light, which is diffused in the direction of the field at the angle θ = VIH (Verdet’s law), where / is the length of the beam’s path in m (or cm), H is the strength of the magnetic field in amperes (A) per m (or oersteds), and V is Verdet’s constant—the specific magnetic rotation—in radians per A (or radians per oersted cm).