Millimeter-Wave Acoustic Transducers

This project was focused on a program to realize efficient systems for generating and detecting coherent phonons with millimeter wavelengths. The primary task was the realization of transducers that are capable of converting electromagnetic energy to acoustic energy in this frequency region. In order to increase the operating frequency, the components of the acoustic transducer must be redesigned. Instead of the single layer ZnO acoustic transducers used below 10 GHz, multilayer ZnO acoustic transducers must be used to generate sufficient power at frequencies above 24 GHz. In association with all of this we have continued to investigate the nature of acoustic wave propagation in liquid helium. Acoustics, Transducers, Liquid Helium, Parametric amplification, Zinc-oxide.