Electromagnetic generation of acoustic waves near second-order magnetic phase transitions of the “order-disorder” and “order-order” type

Abstract

In this work, we theoretically and experimentally established the common feature of the evolution of the efficiency of the electromagnetic generation of acoustic waves near the temperatures of second-order magnetic phase transitions characteristic of both the “order-disorder” (Curie point in isotropic ferromagnets) and “order-order” (easy-axis-angular-phase and angular-phase-easy-plane) transitions in uniaxial magnets, which consists in the fact that the peak of efficiency corresponds precisely to these temperatures at any values of the magnetic field even if in a magnetic field these temperatures cease to be the points of phase transitions.