Design of a surface acoustic wave mass sensor in the 100GHz range

A design for photoacoustic mass sensors operating above 100GHz is proposed. The design is based on impulsive optical excitation of a pseudosurface acoustic wave in a surface phononic crystal with nanometric periodic grating and on time-resolved extreme ultraviolet detection of the pseudosurface acoustic wave frequency shift upon mass loading the device. The present design opens the path to sensors operating in a frequency range currently unaccessible to electro-acoustical transducers, providing enhanced sensitivity, miniaturization, and incorporating time-resolving capability while forgoing the piezoelectric substrate requirement. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729624]