Phonon dispersion relation of Si membranes (with thicknesses, d, from 400 nm down to ∼ 8 nm) measured by inelastic light scattering and plotted on one curve by representing the phase velocity as a function of the dimensionless q//•d. The ultra-thin nature of the membranes results in a slow phase velocity for the fundamental flexural modes, with a phase velocity dowsn to 300 m s-1 recorded for the ∼ 8 nm membrane. This is 15 times smaller than the comparable Rayleigh Wave
Courtesy:
J. Cuffe et al
Source:
nanoICT Strategic Research Agenda - Annex 1 - Nanophotonics and Nanophononics
