New Low Loss High Coupling Mode up to 1 GHz on LiNbO3.

摘要

Experimental measurements of 345 MHz surface acoustic waves propagating along the X-axis of Z-cut lithium niobate have revealed the existence of a low-loss, high-coupling mode whose insertion loss is less than the Rayleigh-type surface acoustic wave. When the double electrode of quarter-wavelength transducers were excited at the third overtone at 1035 MHz, the insertion loss of this mode was about 10 dB less than that of the SAW. The experimentally observed velocity of this mode was 4375 m/sec, considerably higher than the metalized SAW velocity of 3800 m/sec, but in excellent agreement with the theoretical calculated metalized pseudo SAW velocity. The experimentally determined coupling (v/v) for this mode is almost a factor of three times that of the SAW. This volume mode is in low-loss, broadband signal processing devices. (Author)