Date of this Version
Huijing He. "Effects of mode coupling on the admittance of an AT-cut quartz thickness-shear resonator" Chinese Physics B Vol. 22 Iss. 4 (2013) p. 047702-1 - 047702-6
We study the effects of couplings to ﬂexure and face-shear modes on the admittance of an AT-cut quartz plate thickness-shear mode resonator. Mindlin’s two-dimensional equations for piezoelectric plates are employed. Electrically forced vibration solutions are obtained for three cases: pure thickness-shear mode alone; two coupled modes of thickness shear and ﬂexure; and three coupled modes of thickness shear, ﬂexure, and face shear. Admittance is calculated and its dependence on the driving frequency and the length/thickness ratio of the resonator is examined. Results show that near the thickness-shear resonance, admittance assumes maxima, and that for certain values of the length/thickness ratio, the coupling to ﬂexure causes severe admittance drops, while the coupling to the face-shear mode causes additional admittance changes that were previously unknown and hence are not considered in current resonator design practice.