Design of a Thickness Sensor Based on a One-Dimensional Phononic Crystal

Nowadays, sensor technology has attracted great interest in various domains. In this ‎work, we have analyzed a one dimensional phononic crystal made by the stack of N bilayers of ‎‎(LiNbO3/SiO2). The sensor design consists of a one dimensional phononic crystal structure with a ‎defect layer inserted in the middle. Using the Transfer Matrix Method (TMM), the transmission ‎spectrums of acoustic waves are calculated and plotted. In this work, we are interested in the ‎resonance peak that is transmitted inside the phononic band gap. The results obtained show clearly that the resonant frequency of the measured ‎transmission peak is very sensitive to the layer defect properties. This proves that such structure offers a new platform for sensing ‎applications.