Dear Steven,
I am calculating the transmission of a photonic crystal slab. My
system is similar as Fan's article (PRB 65, 235112, analysis of guided
resonances in photonic crystal slabs). The computational cell is large and
time-consuming. I want to exploit the symmetry to speed up the computation.
I have read the meep manual about symmetry. The square lattice has mirror
symmetry about x, y axes, 90 degree rotaitional symmetry. But the source is
Ey or Ex, I am confused by these. I don't know how to set the symmetry.
Could you suggest me about this? Thank you very much! The following is my
ctl file
(define-param n1 2.05)
(define-param eps (* n1 n1))
(define-param n2 1.0)
(define-param eps2 (* n2 n2))
(define-param r 0.1)
(define-param thick 0.4)
(define-param no-slab? false)
(set! geometry-lattice (make lattice (size 1 1 5)));the computional cell
(set! geometry
(if no-slab?
(list
(make block
(center 0 0 0)
(size 1 1 5)
(material (make dielectric (epsilon 1)))))
(list
(make block
(center 0 0 0)
(size 1 1 thick)
(material (make dielectric (epsilon eps))))
(make cylinder
(center 0 0 0)
(radius r)
(height thick)
(material (make dielectric (epsilon eps2)))))))
(define-param fcen 0.9) ; pulse center frequency
(define-param df 0.8) ; pulse width (in frequency)
(set! sources
(list
(make source
(src (make gaussian-src (frequency fcen) (fwidth df)))
(component Ey)
(center 0 0 1.25)
(size 1 1 0))))
(set! k-point (vector3 0 0 0))
(set! pml-layers (list (make pml (direction Z) (thickness 1.0))))
(set-param! resolution 50)
(define-param nfreq 1000) ; number of frequencies at which to compute flux
(define trans
(add-flux fcen df nfreq
(make flux-region (center 0 0 -1.0) (size 1 1 0) (direction
Z))))
(define refl
(add-flux fcen df nfreq
(make flux-region (center 0 0 1.0) (size 1 1 0) (direction Z))))
(if (not no-slab?) (load-minus-flux "refl-flux" refl))
(run-until 400
(at-beginning output-epsilon)
(at-end output-efield-y))
(if no-slab? (save-flux "refl-flux" refl))
(display-fluxes trans refl)
_______________________________________________
meep-discuss mailing list
[email protected]
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
