Suppression of stimulated phonon emission in ruby by a
magnetic-field gradient
P. A. Fokker,(a) R. S. Meltzer,(b) Y. P.
Wang,(b) J. I. Dijkhuis,(a) and H. W. de
Wijn(a)
(a) Faculty of Physics and Astronomy, and Debye Research
Institute, Utrecht University, P.O. Box 80.000, 3508 TA Utrecht, The
Netherlands
(b) Faculty of Physics and Astronomy, University of Georgia,
Athens, Georgia 30602, USA
It is demonstrated that a magnetic field gradient can suppress amplified
stimulated emission of phonons taking place within the Zeeman-split
E(2E) doublet of Cr3+ in 700-ppm ruby.
The doublet is initially inverted by selective pulsed optical pumping.
The field gradient produces a gradient in the transition frequency,
thereby reducing the gain of the amplifying medium. The experiments are
described with rate equations in which the gain is accounted for by the
interaction length over which the phonons remain at resonance.