COMSOL Multiplhysics (R) Version 5.1

-SiO2-
permittivity 3.9
permeability 1.0
conductivity 0.0

-Au-
permittivity 1.0
permeability 1.0
conductivity ~DRUDE~

~Drude parameters~
DC conductivity 2.7e7 S/m
scattering rate 5 THz


-Graphene-
permittivity 2.54
permeability 1.0
conductivity ~DRUDE~

~Drude parameters~
DC conductivity variable
scattering time 15 fs 

-Si-
permittivity 1.0
permeability 1.0
conductivity Drude

~Drude parameters~
DC conductivity 1 / (25 Ohm cm)
scattering time 50fs