Phonon echoes and amplification of ultrasonic waves in a microwave electric field

Abstract

This paper presents a theoretical discussion of the phonon (two-pulse) echo and amplification of ultrasonic waves in a microwave electric field. A formula for the power of the phonon echo of $N\mathrm{th}$ order is presented together with a formula giving the amplification of ultrasound in a microwave electric field. The relationship between the polarization of the phonon echo wave, the incident wave, and the direction of the externally applied electric field is pointed out. New predictions on the generation of phonon echoes whose frequency and polarization differ from the frequency and polarization of the primary wave are made.