Dear Steven and meep users,
Hello,
I'm simulating a 2D-PhC based Channel Drop Filter by meep. I have reasonable
result for short time simulation, but in long time runs, I get a divergence.
I want to know what is the physical reason and how I can solve it. The
problem even exists in propagation in a triangular lattice straight
waveguide.
Another strange event is that there is no problem in long time simulation
for square lattice PhCs. My ctl file for a straight waveguide is as follow
and the simulation is done in 30 seconds. Devergence happens for times mor
that 300.
Could somebody help me?
(define-param A 1); lattice constant
(define-param sy (* A (* 21 (/ (sqrt 3) 2)))) ; size of cell in X direction
(define-param sx (* A 11)) ; size of cell in Y direction
(set! geometry-lattice (make lattice (size sx sy no-size)))
(define-param res 10) ; resolution
(define-param trun 500) ; time of simulation
(set! geometry-lattice (make lattice (size sx sy no-size)))
(define-param px A)
(define-param py (* (/ (sqrt 3) 2) A))
(define-param r (* A 0.35))
(define-param nair 1.0)
(define-param nb 3.4)
(define airrod (make dielectric (index nair)))
(set! default-material (make dielectric (index nb)))
(set! geometry (list .....))
(define-param fcen (/ 0.25 A)) ; pulse center frequency
(define-param df (/ 0.05 A)) ; pulse width (in frequency)
(define-param dft (/ 0.003 A)) ; trans width (in frequency)
(set! sources (list
(make source
(src (make gaussian-src (frequency fcen) (fwidth df)))
(component Hz)
(center (* -4 px) 0)
(size 0 py))))
(set! pml-layers (list (make pml (thickness (* 1 A)))))
(set-param! resolution res)
(define-param nfreq 1000) ; number of frequencies at which to compute flux
(define trans ; transmitted flux
(add-flux fcen dft nfreq (make flux-region (center (* 4 px) 0) (size 0
py))))
(run-sources+ trun (at-beginning output-epsilon))
(display-fluxes trans)
a. noaina
_______________________________________________
meep-discuss mailing list
[email protected]
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
