simple question about the paper linear waveguides in photonic crystal slabs

mahmoud hamoud <[email protected]>
Newsgroups gmane.comp.science.photonic-bands
Message-ID <[email protected]>
Hi Dear Steven and mpb users,
I have reproduced all the figures of the paper, but i have a problem with figure 13. Steven says that for each radius, there are two or three guided bands, and my results shows more than three guided bands in the gap area. i pass my ctl file and i appreciate any help
thanks for the guidance
best regards,

(define-param h 0.5) ; the thickness of the slab
(define-param eps 12.0) ; the dielectric constant of the slab
(define-param loweps 2.0) ; the dielectric constant of the substrate
(define-param r 0.3) ; the radius of the holes
(define-param R 0.15) ; the radius of the defect
(define-param supercell-h 6) ; height of the supercell
(define-param supercell-y 7) ; the (odd) number of lateral supercell periods
; triangular lattice with vertical supercell:
(set! geometry-lattice (make lattice (size 1  supercell-y supercell-h)
                         (basis1 (/ (sqrt 3) 2) 0.5)
                         (basis2 (/ (sqrt 3) 2) -0.5)))

(set! geometry
      (list (make block (material (make dielectric (epsilon loweps)))
            (center 0 0 -1.65) (size 0.15 0.15 2.7)) 
            (make block (material (make dielectric (epsilon loweps)))
            (center 0 0 1.65) (size 0.15 0.15 2.7)) 
            (make block (material (make dielectric (epsilon eps)))
            (center 0 0 0) (size infinity infinity h)) 
        (make cylinder (material air)
          (center 0) (radius r) (height supercell-h))))
(set! geometry 
      (append
       ; duplicate the bulk crystal rods over the supercell:
       (geometric-objects-lattice-duplicates geometry 1 1 supercell-h)

       ; add a rod of air, to erase a row of rods and form a waveguide:
       (list 
    (make cylinder (center 0) (radius r) (height supercell-h)
          (material (make dielectric (epsilon eps)))))
      ; add a rod of air, to erase a row of rods and form a waveguide:
       (list 
    (make cylinder (center 0) (radius R) (height supercell-h)
          (material air)))))


; 1st Brillouin zone of a triangular lattice:
(define Gamma (vector3 0 0 0))
(define K' (lattice->reciprocal (vector3 0.5 0 0))) ; edge of Brillouin zone.

(define-param only-K false) ; run with only-K=true to only do this k-point
(define-param k-interp 4)   ; the number of k points to interpolate
(if only-K
    (set! k-points (list K))
    (set! k-points (interpolate k-interp (list Gamma K'))))

(set-param! resolution (vector3 20 32 20))
(set-param! mesh-size 7)
(set-param! num-bands 12)

; Run even bands, outputting fields only at the K point:
(run-zeven)
(display-eigensolver-stats)

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