Dear Mr. Johnson and MPB users
I intend to simulate the dispersion diagram of coupled cavity located beside a
line defect of the air holes on the epsilon. like below:
o= holes
x= defect
ooooooooooooooooooo....
ooooxooooxooooxoooo....
ooooooooooooooooooo....
xxxxxxxxxxxxxxxxxxxxx....
ooooooooooooooooooo....
ooooooooooooooooooo....
ooooooooooooooooooo...
My questions:
1- it seems I have to define the supercell with the (size 5 7 nosize). and
remove 5 holes from middle (to make a waveguide) and one from upper line(to
make a point defect, (as it is clear in my ctl attached file) it will be OK. is
it correct?
2-if I define supercell (size 10 7 nosize), and remove 10 holes from middle (to
make a waveguide) and two from upper line with (to make two point defects with
4 a far from each other, (as it is clear in my second ctl attached file) the
dispersion curves should be same as previous one, but they are different!! why?
3- if I want to modify ctl file for triangular lattice, are the modification on
(basis1 (/ (sqrt 3) 2) 0.5) and (basis2 (/ (sqrt 3) 2) -0.5) enough or I
have to modify any other part of ctl file? (unfortunately every time I confuse
between the coordination systems lattice, Cartesian , .... )
regards
Hassan
==============
;first ctl file, 5*7
(set! default-material (make dielectric (epsilon 12)))
(define Gamma' (vector3 0 0 0))
(define K' (lattice->reciprocal (vector3 0.5 0 0))) ; edge of Brillouin zone.
(set! k-points (interpolate 4 (list Gamma' K')))
(set! num-bands 10)
(set-param! resolution 32)
(set! geometry-lattice (make lattice
(size 5 7 no-size)))
(set! geometry (list (make cylinder
(center 0 0 0) (radius r) (height infinity)
(material air))))
(set! geometry
(append
(geometric-objects-lattice-duplicates geometry)
(list ; add a row of rods (epsilon) on Center, to make a waveguide:
(make cylinder (center -2 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center -1 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 0 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 1 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 2 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
; add a rod (epsilon) on _-2 -2 0), to make a cavity:
(make cylinder (center -2 -2 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
)))
(run-te)
==================================
; second ctl, super cell (10*7)
(set! default-material (make dielectric (epsilon 12)))
(define Gamma' (vector3 0 0 0))
(define K' (lattice->reciprocal (vector3 0.5 0 0))) ; edge of Brillouin zone.
(set! k-points (interpolate 4 (list Gamma' K')))
(set! num-bands 10)
(set-param! resolution 32)
(set! geometry-lattice (make lattice
(size 10 7 no-size)))
(set! geometry (list (make cylinder
(center 0 0 0) (radius r) (height infinity)
(material air))))
(set! geometry
(append
(geometric-objects-lattice-duplicates geometry)
(list ; add a row of rods (epsilon) on Center, to make a waveguide:
(make cylinder (center -5 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center -4 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center -3 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center -2 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center -1 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 0 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 1 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 2 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 3 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 4 0 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
; add two rod (epsilon) on _-5 -2 0 and 0 -2 0 , to make a
cavity:
(make cylinder (center -5 -2 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
(make cylinder (center 0 -2 0) (radius r) (height infinity)
(material (make dielectric (epsilon eps)))
)))
(run-te)
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