ON THE INTENSITY OF SHOCK-INITIATED MAGNETOELASTIC OSCILLATIONS ARISING IN IRON BORATE SINGLE-CRYSTALS DURING PULSED MAGNETIZING OR MAGNETIZATION-SWITCHING PROCESSES

The intensities of magnetoelastic oscillations accompanying pulsed 180 degrees and 90 degrees magnetization switching of iran borate single crystals as well as pulsed magnetization of the crystals from a demagn etized state (with teres total magnetic moment) are compared for the f irst time. The amplitude A(1) of the oscillations of the signal obtain ed from the experimental sample by the induction method is adopted as a measure of the intensity of the magnetoelastic oscillations. ft is f ound that for the same pulse heights of the magnetic field H exciting the magnetization-switching or magnetizing process, the amplitudes A(1 ) of the oscillations observed in 90 degrees magnetization-switching a nd initial-magnetization processes have practically the same value, wh ich is root 2 times smaller than the amplitude of the oscillations obt ained in 180 degrees magnetization switching (reversal). It is conclud ed on the basis of the result obtained that the intensity of the magne toelastic oscillations is virtually independent of the initial state o f the single crystal and is determined mainly by the energy density De lta M . H acquired by the magnetic subsystem of the crystal from the e xternal field (Delta M is the change in magnetization). Hence it follo ws that when iron berate is used in fast modulators for Mossbauer gamm a rays it is preferable to use the 90 degrees magnetization-switching regime rather than the magnetization regime as has been done until ver y recently. (C) 1998 American Institute of Physics. [S1063-7842(98)029 09-2].