Figure 4: Motion transduction measurement and plasmonic origin verification.
From: Nanomechanical motion transduction with a scalable localized gap plasmon architecture
Calibrated displacement spectrum for the (a) cantilever and (b) beam; insets show the measured mechanical frequency as a function of input power. (c) Spectral reflectivity for the third, beam device; insets show the motion power spectral density measured at each wavelength. (d) Measured dimensionless motion signal strength 
as function of laser wavelength detuning. Signal-strength measurements are performed with an optical power of 1.25 mW delivered to the sample, which due to experimental limitations can only be achieved for detuning ranging from −10 nm to +25 nm. The grey line is the theoretical signal curve; error bars are the s.e. derived from Lorentzian fitting to the measured electrical power spectral density.
