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Anonymous

Problem in defining a dispersive material in Meep (Gold)

Hello, 
 I am contacting you regarding an issue I am facing in Meep. I am trying to define dispersion relation of Gold in Meep using Lorentz-Drude model. After running the code, I don't  receive any error message and the simulation continues, however the software does not recognize my defined material and considers all the materials as air (epsilon=1).  here is my code, I would be thankful if you could let me know how I can fix the problem.
Thanks

(define-param a 0.10) ; inner radius
(define-param b 0.12) ; outer radius
(define-param pad 3) ; padding between waveguide and edge of PML
(define-param dpml 3) ; thickness of PML
(define-param l 1) ; length of simulation
(define sr (+ b pad dpml)) ; radial size (cell is from 0 to sr)
(define sl (+ l pad pad dpml dpml)) ; longitudinal size
(set! dimensions CYLINDRICAL)
(set! geometry-lattice (make lattice (size sr no-size sl)))
(set-param! m 0)

(define myAu (make dielectric (epsilon 1)
(E-susceptibilities
(make lorentzian-susceptibility
(frequency 1e-20) (gamma 0.042747) (sigma 4.0314e+41))
(make lorentzian-susceptibility
(frequency 0.33472) (gamma 0.19438) (sigma 11.363))
(make lorentzian-susceptibility
(frequency 0.66944) (gamma 0.27826) (sigma 1.1836))
(make lorentzian-susceptibility
(frequency 2.3947) (gamma 0.7017) (sigma 0.65677))
(make lorentzian-susceptibility
(frequency 3.4714) (gamma 2.0115) (sigma 2.6455))
(make lorentzian-susceptibility
(frequency 10.743) (gamma 1.7857) (sigma 2.0148))
)))

(set! geometry (list
 (make block
 (center (/ sr 2) no-size 0 ) (size sr infinity l) (material myAu))
 (make block
 (center (/ b 2) no-size 0) (size b infinity l) (material air))
 (make block

 (center (/ a 2) no-size 0) (size a infinity l) (material myAu))
))
(set! pml-layers (list (make pml (thickness dpml))))
(set-param! resolution 200)
(define-param fcen 1.5) ; pulse center frequency
(define-param df 2.9) ; pulse width (in frequency)
(set! sources (list
(make source
(src (make gaussian-src (frequency fcen) (fwidth df)))
(component Er) (center 0 0 -1))))
(define-param nfreq 1000) ;number of frequencies at which to compute flux
(define trans ; transmitted flux
(add-flux fcen df nfreq
(make flux-region
(center (/ (+ a b) 2) 0 (/ l 2))
(size (- b a) no-size no-size)
)))
(run-sources+ (stop-when-fields-decayed 50 Ez
(vector3 0 0 (+(/ l 2) 0.5)) 1000)
(at-beginning output-epsilon)
(at-end output-efield-z))
(display-fluxes trans)

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