Department of Materials Science and Engineering, University of Arizona, Tucson, Arizona 85721, USA.
J Acoust Soc Am. 2011 Oct;130(4):1919-25. doi: 10.1121/1.3631627.
A phononic crystal (PC) consisting of a square array of cylindrical polyvinylchloride inclusions in air is used to construct a variety of acoustic logic gates. In a certain range of operating frequencies, the PC band structure shows square-like equi-frequency contours centered off the gamma point. This attribute allows for the realization of non-collinear wave and group velocity vectors in the PC wave vector space. This feature can be utilized to control with great precision, the relative phase between propagating acoustic waves in the PC. By altering the incidence angle of the impinging acoustic beams or varying the PC thickness, interferences occur between acoustic wave pairs. It is recognized that information can be encoded with this mechanism (e.g., wave amplitudes/interference patterns) and accordingly to construct a series of logic gates emulating Boolean functions. The NAND, XOR, and NOT gates are demonstrated with finite-difference time-domain simulations of acoustic waves impinging upon the PC.
声子晶体（PC）由空气 中的圆柱状聚氯乙烯夹杂形成的正方形阵列组成，可用于构建各种声 学逻辑门。在一定的工作频率范围内，PC 的能带结构显示出以伽马点为中心的类正方形等频轮廓。这一特性允许在 PC 波矢空间中实现非共线的波和群速度矢量。这一特点可用于非常精确地控制 PC 中传播声波之间的相对相位。通过改变入射声波的入射角或改变 PC 的厚度，声波对之间会发生干涉。人们认识到，可以利用这种机制（例如，波幅/干涉模式）进行信息编码，并相应地构建一系列模拟布尔函数的逻辑门。通过对声波撞击 PC 的有限差分时域模拟，演示了 NAND、XOR 和 NOT 门。
