Laser Excitation of Surface Acoustic Waves in Diamond Using Embedded Microstructure Based on the Graphitized Layer

Abstract

Ion-implanted and graphitized layers in diamond are considered as a key element of promising acousto-electronic devices, micro- and nano-electromechanical systems operating in the gigahertz frequency range. That is why their acoustical and photo-acoustical properties are of interest. In this work, we show that graphitized layers in diamond irradiated with femtosecond laser pulses are efficient generators of not only bulk but also surface waves. The nature of these waves is similar in structure to Rayleigh waves propagating along a free flat boundary of a half-space. In contrast to the undamaged diamond surface, the propagation of such a wave along the diamond surface with a buried graphitized layer leads to a considerable “spreading” of the surface wave caused by dispersion.