UNIDIRECTIONAL ULTRASONIC AMPLIFICATION IN A LASERhyphen;PUMPED MEDIUM

摘要

Unidirectional parametric amplification of an ultrasonic wave propagating in a laserhyphen;pumped birefringent medium was observed. Usingxhyphen;cut quartz pumped by a ruby laser, power gains approaching 10 dB were measured at ultrasonic frequencies in the neighborhood of 75 MHz. The effect was identified as a ``coflow''hyphen;type parametric interaction.