(yxl)21.82° LiNbO3 pseudo-LFE acoustic wave sensors

摘要

Previous studies showed that Lateral field excitation (LFE) devices on AT-cut quartz are sensitive to liquid electrical property changes. However, the sensitivity of the device is limited due to the low piezoelectric coupling factor. In the present study, a pseudo-LFE sensor on (yxl)21.82° lithium niobate is investigated both theoretically and experimentally. It is found that the (yxl)21.82° LiNbO₃ LFE device works on pseudo-LFE mode with a very high piezoelectric coupling factor of 24.41%, which is almost 3 times higher than that of AT-cut quartz. The experimental result also shows that the device is about 20 times more sensitive to liquid conductivity changes compared to AT-cut quartz LFE devices.