Abstract:
The invention of electric diodes, which were the first devices to enable the rectification of current flux, marked the emergence of modern electronics, led to worldwide revolutions in many aspects, and eventually changed our daily lives significantly. Compared with electricity, the acoustic wave is an important form of classical wave that is more ubiquitous in nature and has a much longer research history. It is therefore apparent that the counterpart devices for rectifying acoustic propagation, if they could be successfully designed and fabricated, would have deep implications for acoustic devices and applications, and the field of acoustics in general. This article presents a comprehensive discussion of the theoretical design and experimental realization of an acoustic diode that consists of a superlattice and a nonlinear acoustic medium.