Multidimensional control of surface acoustic wave generation via programmable interdigital transducer arrays.

Abstract

Fixed interdigital transducers (IDTs) are commonly limited to only generate a single type of surface acoustic wave (SAW). Here, we present a programmable IDT array architecture for multidimensional SAW generation, based on standard and chirped IDT array designs. Forty independently addressable IDT units are each modulated by a double-pole-double-throw switch to enable binary phase inversion. This system generates diverse SAW waveforms including non-diffracting Airy SAWs and dynamically focused SAWs. We achieve two-dimensional focus manipulation with sub-wavelength precision and extended focal depth, enabled by time-division multiplexing with chirped IDTs. By combining spatial phase encoding with spectral frequency multiplexing, our approach demonstrates multidimensional control over SAW generation, providing a platform for adaptive acoustic field control in applications such as reconfigurable microfluidics, tuneable metamaterials, and multifrequency sensing systems.