Nance, Douglas V Dr CIV USAF AFMC AFRL/RWWC <douglas.nance <at> eglin.af.mil>
writes:
>
> Hello everyone,
>
> Does anyone know where a MPB ctl file is posted for the stacked 3D
> photonic crystal shown in Figure 10, p. 106 of the Joannopoulos,
> Johnson, Winn and Meade Photonic Crystals textbook?
>
> I would like to compare the ctl file with one that I am building.
>
> Thanks very much.
>
> Doug Nance
>
Greetings,
I am new to this field, so after agonizing over my own question for several
hours, I carefully reread the caption of figure 10 in the PC text. It says
that the structure is created by an array of overlapping air cylinders set in
an FCC lattice. Each cylinder is oriented in the (111) direction. As it
happens, this fact seems to be very important. I accomplished this alignment
(so I believe) in my ctl file, and I can see the hexagonal orientation of the
cylinders when I post-process the epsilon.h5 file. My ctl file is shown below.
I attempted to calculate the band structure cited in Galusha, Jorgensenn
Bartl, "Diamond-structured titania photonic-bandgap crystals from biological
templates", Adv. Mater. 2010, 22, 107-110. The bandgap diagram (Fig. 2c in the
paper) looks encouraging. I can't figure out a way to upload the diagram here.
Any constructive comments/criticisms of my ctl file or of this problem are
welcome. Thank you.
; Classic fcc lattice
; Air cylinders in a dielectric medium
(set! geometry-lattice (make lattice
(basis-size (sqrt 0.5) (sqrt 0.5) (sqrt 0.5))
(basis1 0 1 1)
(basis2 1 0 1)
(basis3 1 1 0)))
; Corners of the irreducible Brillouin zone for the fcc lattice
; in a canonical order
(set! k-points (interpolate 4 (list
(vector3 0 0.5 0.5) ; X
(vector3 0 0.625 0.375) ; U
(vector3 0 0.5 0) ; L
(vector3 0 0 0) ; Gamma
(vector3 0 0.5 0.5) ; X
(vector3 0.25 0.75 0.5) ; W
(vector3 0.375 0.75 0.375)))) ; K
; define parameters
(define-param eps 5.29) ; dielectric constant for block
(define-param r 0.27) ; cylinder radius
(define-param h 0.89) ; cylinder height
(define dair (make dielectric (epsilon 1.0)))
(set! default-material (make dielectric (epsilon eps)))
; A diamond lattice has two atoms per unit cell
(set! geometry (list (make cylinder (center 0 0 0)
(radius r)
(height h)
(axis (cartesian->lattice (vector3 1 1 1)))
(material dair))))
; (make cylinder (center 0.375 0.125 0.375)
; (radius r)
; (height h)
; (axis (cartesian->lattice (vector3 1 1 1)))
; (material dair))))
(set-param! resolution 32)
(set-param! mesh-size 10)
(set-param! num-bands 5)
(run)
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