METHOD AND APPARATUS FOR MEASURING MAGNETIC FILM MAGNETIZATION CURVE

摘要

PURPOSE:To detect longitudinal and lateral Kerr effect signals simultaneously by obtaining a lateral Kerr effect signal from one part of a reflected light divided into two from a magnetic film and a longitudinal Kerr effect signal after a longitudinal Kerr effect-mixed lateral Kerr effect signal is obtained from the other part thereof with its transmission through a light detection element to offset both of the lateral Kerr signals. CONSTITUTION:A laser beam from a laser light source 1 is made to pass through a polarizer 2 and reflect on a magnetic film sample 10 and divided into beams L1 and L2 with a half mirror 5. The beam L1 is passed through an optical attenuator 6, the first photoelectric converter 8 and a preamplifier/buffer 9 to obtain a lateral Kerr effect signal (a). The beam L2 is passed through a light detecting element 15, the second photoelectric converter 17 and a preamplifier/ buffer 18 to obtain a longitudinal Kerr effect signal (b) plus lateral Kerr effect signal (a'). The signal (a') is made equivalent to the signal (a') with a variable resistor 12 and then, both of the signals are offset with a differential amplifier 13 to output a longitudinal Kerr effect signal.