SUPPRESSION OF STIMULATED PHONON EMISSION IN RUBY BY A MAGNETIC-FIELDGRADIENT

It is demonstrated that a magnetic-field gradient can suppress amplifi ed stimulated emission of phonons taking place within the Zeeman-split (E) over bar((2)E) doublet of Cr3+ in 700 ppm ruby. The doublet is in itially inverted by selective pulsed optical pumping. The field gradie nt produces a,gradient in the transition frequency, thereby reducing t he gain of the amplifying medium. The experiments are described with r ate equations in which the gain is accounted forby the interaction len gth over which the phonons remain at resonance.