Au backreflector

G:\My Drive\product\v1\electrostatics\electrostatics_capacitor_scikit_fem.ipynb

"box_width": 20.0 * um,
"lower_insulator_thickness": 10 * um,
"electrode_thickness": 100.0 * nm,
"gap_width": 1 * um,
"bridge_thickness": 200.0 * nm,
"top_cladding_thickness": 2.0 * um,
"n_lower": 1.45,
"n_bridge": 1.8,
"n_top": 1.5,
"v_right": 10.0,

Bridge center electric field: |E| = 7.279e+06 V/m $Ex = -7.278e+06 V/m, Ez = -1.114e+05 V/m$

Quarter wavelength insulator

"box_width": 20.0 * um,
"lower_insulator_thickness": .78/4 * um,
"electrode_thickness": 100.0 * nm,
"gap_width": 1 * um,
"bridge_thickness": 200.0 * nm,
"top_cladding_thickness": 2.0 * um,
"n_lower": 1.45,
"n_bridge": 1.8,
"n_top": 1.5,
"v_right": 10.0,

Bridge center electric field: |E| = 7.111e+06 V/m $Ex = -6.163e+06 V/m, Ez = -3.547e+06 V/m$