Waveguide in PC slabs (triangular lattice)

Dear Steven,
    I think you don't understand what I mean in the 2nd email (not 1st email): I defined my computation cell: 1x7x4, the line defect waveguide is formed by a row of changing holes along the "x" direction. I paste my *.ctl as below:
   
  (set! geometry-lattice (make lattice 
  (basis1 (/ (sqrt 3) 2) 0.5)
  (basis2 (/ (sqrt 3) 2) -0.5)
  (size 1 7 4)))
  (define-param h 0.5) ; the thickness of the slab
  (define-param eps 12) ; the dielectric constant of the slab
  (define-param r 0.3) ; the hole radius in the bulk crystal
  (define-param ra 0.40) ; the hole radius in the line defect
  (set! geometry
           (list (make block (material (make dielectric (epsilon 1)))
                                     (center 0 0 0) (size 1 7 4))
                 (make block (material (make dielectric (epsilon eps)))
                                    (center 0 0 0) (size 1 7 h))
                (make cylinder (material air) (center 0 0 0) (radius r) (height 4))
  ))
  (set! geometry 
         (append
                      (geometric-objects-lattice-duplicates geometry)
               (list
                       (make cylinder (center 0 0 0) (radius ra) (height 4)
                       (material air))
  )))
  (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')))
  (define-param extra-bands 5)
  (set! num-bands (+ 7 extra-bands))
  (set-param! resolution 32)
  (run-zeven (output-at-kpoint (list-ref k-points (quotient (length k-points) 2))
                     fix-hfield-phase output-hfield-z))
  
I don't understand why I am wrong? Please, help me?
   
  Many thanks,
  Nils Jensen

 
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