Hey All, I am John Bordelon from Louisiana State University Electrical Engineering department. I am working on scaling my simulation of a microring resonator up to 3-D and am running into problems. The first is that for some reason the waves are not being confined inside the waveguide. In the video created from the code below, the wave as it just sort of dissipates into free space (and eventually the PML). I have also tried with just a single 3-D waveguide but still am having the same non-confined waves problem.
Perhaps it has to do with my source? For propagation in the x direction, I assumed I would still use (component Ez), as with the 2-D. But maybe I am wrong. Here is the code. Any help is greatly appreciated. (define-param n 3.4) ;index ofwaveguide (define-param fcen .6452) ; frequency of source (define-param L 20.94) ; holds distance (define-param gap .0415) ; gap is 41.5nm (define-param fspread .02) ; spread in gaussian freq range (define-param nfreq 1000) ; number of frequencies at which to compute flux (define-param rho 3.3346) ; radius of circles in track (define-param gap_wg .17) ; this is the gap between ring and waveguide (define-param gap_index .035) ; this is the gap bw index modulator and ring (define-param guide_z .2) (define-param guide_r .2) ;this is the radial thickness of ring (define-param size_z 2) (define-param size_x 10) (define-param size_y 10) (define-param pml_thickness 2) ; remember that to create the index modulator I can use the top two ; cylinders inserted to create a quarter circle a distance above the ring ; with the same z projection (set! geometry-lattice (make lattice (size (+ pml_thickness size_x) (+ pml_thickness size_y) (+ pml_thickness size_z)))) (set! geometry (list (make cylinder (center 0 0 0) (height guide_z) (radius rho) (material (make dielectric (epsilon 11.7)))) (make cylinder (center 0 0 0) (height guide_z) (radius (- rho guide_r)) (material air)) ; possibly insert modulator in here, omit now for testing (make block (center 0 (+ rho guide_r gap_wg) 0) (size infinity guide_r guide_z) ; size is given as (size x y z) (material (make dielectric (epsilon 11.7)))) (make block (center 0 (- (+ rho guide_r gap_wg)) 0) (size infinity guide_r guide_z) ; size is given as (size x y z) (material (make dielectric (epsilon 11.7)))) )) (set! sources (list (make source (src (make gaussian-src (frequency fcen) (fwidth fspread))) (component Ez) (center -4 (+ rho guide_r gap_wg) 0 ) (size 0 .05 .05) (cutoff 15)))) (set! pml-layers (list (make pml (thickness 1)))) (set! resolution 20) (use-output-directory) (run-until 400 (at-beginning output-epsilon) (to-appended "ez" (at-every 10 output-efield-z))) Thanks all, John
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