Numerical and experimental investigation SAW in langasite

The present paper contains the complete numerical investigation of surface acoustics waves in langasite. The results are comprehensive contour-map and three-dimensional loci for velocity (Vo,Vm), beam steering (/spl theta//sup 1/), electromechanical coupling factor (K/sup 2/), first and second temperature derivatives of delay times (TCD1, TCD2). Optimal cuts for multimode resonators (TCD1=0), for bandpass filter (K/sup 2/=0.54%) and for sensors (TCD1=32.82 ppm//spl deg/C) are determined. The rotated Z+25/spl deg/ cut has large K/sup 2/=0.26% and TCD1=0 at the room temperature. The surface transverse wave that propagates over this cut in X+90/spl deg/ exists only at the metalized surface.