A NEW METHOD FOR THE MEASUREMENT OF HYSTERESIS LOOPS IN THE NEAR-SURFACE LAYER OF FERROMAGNETS

A method for the measurement of hysteresis loops in a thin near-surfac e layer of ferromagnetic substances (10-30 nm thick) is described. The method is based on magneto-optical effects manifested by variations o f intensity of reflected light whose polarization plane is rotated wit h respect to s- and p-polarizations. These effects are measured by mod ulation techniques based on rocking the polarization plane of light wi th a magnetooptical modulator. The sensitivity of measurements of a di fference between the intensities of light reflected from magnetized an d nonmagnetized crystals is similar to 10(-5) in relative units. The t echnique makes it possible to study three components of magnetization at the surface of magnetic materials.