Peculiarities of energy trapping of the UHF elastic waves in diamond-based piezoelectric layered structure. I. Waveguide criterion

It has been established that the ET-effect depends considerably on the mutual location of the n-th overtone's antiresonant frequency fa,n and cut-off frequencies of substrate fs,n−k−1 and fs,n−k where fs,n−k−1 < fa,n < fs,n−k, and k = 0, 1, 2,… is the number of half-length waves to be stowed on the thickness of TFPT. The total violation of the ET-effect will be arisen at the condition f > fs,n−k, when the BAW energy excites the symmetrical or antisymmetrical Lamb waves.