Kotelnikov Institute of Radio Engineering and Electronics of RAS, Moscow 125009, Russia.
Kotelnikov Institute of Radio Engineering and Electronics of RAS, Saratov Branch, Saratov 410019, Russia.
Sensors (Basel). 2023 Jan 6;23(2):648. doi: 10.3390/s23020648.
Backward acoustic waves are characterized by oppositely directed phase and group velocities. These waves can exist in isotropic and piezoelectric plates. They can be detected using a set of interdigital transducers with different spatial periods located on the same piezoelectric substrate. In this paper, the effect of a nonviscous and nonconductive liquid on the characteristics of a first-order backward antisymmetric wave in a YX plate of lithium niobate is studied theoretically and experimentally. It is shown that the presence of liquid does not lead to the transformation or disappearance of this wave. It is shown that these waves are close to the cutoff frequency and are characterized by the presence of a point with zero group velocity. The design of a liquid sensor based on these waves is proposed.
反向声波的特征是相位和群速度方向相反。这些波可以存在于各向同性和压电板中。它们可以使用位于同一压电基板上的具有不同空间周期的一组叉指换能器来检测。本文从理论和实验上研究了非粘性和非导电液体对铌酸锂 YX 板中一阶反向反对称波特性的影响。结果表明，液体的存在不会导致该波的变换或消失。结果表明，这些波接近截止频率，其特征是存在一个群速度为零的点。提出了基于这些波的液体传感器的设计。
