Parametric excitation of magnetoelastic vibrations in hematite single crystals in weak magnetic fields

This paper reports on the results of investigations into the magnetoelastic vibrations excited by radio pulses in thin single-crystal hematite plates according to the scheme of parallel parametric pumping. It is demonstrated that this technique can be used to examine the multimode spectrum of natural vibrations of crystals in weak external magnetic fields H₀ < 200 Oe and to measure some acoustical quantities in this range. By using the parametric amplification of sound, it is established that an increase in the magnetic field is accompanied by the appearance of weakly damped low-intensity modes in the spectrum of natural vibrations.