SENSITIVE METHOD FOR THE MEASUREMENT OF THE KERR MAGNETOOPTIC EFFECT

Apparatus for the measurement of the transverse Kerr magneto-optic effect is described. The instrument was based on a standard research ellipsometer in a polarizer, compensator, sample, analyzer (PCSA) configuration. The light source was a laser whose intensity was acousto-optically modulated. At the same time the magnetization of the magnetic film sample was modulated by the field of a nearby coil. The frequency of the magneto-optic modulation was much less than that of the intensity. Both the intensity and magneto-optic signals were measured as functions of the analyzer and polarizer angles. The automation of the measurement is outlined. The methods are described by means of which the magneto-optic variation in psi and DELTA were calculated. Typical experimental results are presented for ferromagnetic films which were overcoated with a multilayer dielectric stack.