Figure 3: Calculated and measured optomechanical coupling.
From: Nanomechanical motion transduction with a scalable localized gap plasmon architecture
Absolute values of the calculated optomechanical coupling constant gOM/2π (left axis) and |∂λLGP/∂z| (right axis) from FEM modelled reflectivity data (grey circles) and from the semi-analytical model in equation 2 (dashed red line). The inset shows the two-dimensional calculated effective index (circles) and derived reflection phase (squares) as a function of gap; solid lines are fits to exponential functions. The black square shows the experimentally measured cantilever pNEMS optomechanical coupling value. Uncertainty indicates±one standard deviation, corresponding to (2±0.3) THz·nm−1 for optomechanical coupling and (15±1) nm for the full gap range consistent with AFM data for the gap. The error bar for the gap size is determined from the s.e. of the parabolic fit to AFM data (Supplementary Note 5), whereas the error bar for optomechanical coupling corresponds to the propagated error from all sources (Methods).
