SELECTED STUDIES IN MICROWAVE ACOUSTICS.
Final rept., 1 Mar-30 Sep 65,
MICROWAVE LAB STANFORD UNIV CALIF
Pagination or Media Count:
Controlled steering of the direction of a microwave acoustic beam in a ferrite by variation of the magnitude of the dc applied magnetic field was demonstrated. In a ferrimagnetic medium the interaction of acoustic waves with spin waves induces a deviation of the group velocity away from the phase velocity. This effect was demonstrated experimentally by the observation of pulse transmission between offset piezoelectric transducers on the ends of an yttrium iron garnet rod. Transmission occurs under the theoretically predicted conditions on magnetic field intensity and direction. The power-output versus frequency of multiple film hypersonic transducers was calculated by separate computer programs for certain specialized film configurations. A more generalized computer program was developed which is capable of treating configurations of films which are completely arbitrary with respect to material, physical thickness, and ordering of films used. This program assumes no power loss in the materials. Examples of the results of this program are described. Author