headers
Dropbox | 11 May 2013 20:02

Cicero Juliao invited you to check out Dropbox

Hi there,

Cicero Juliao wants you to try Dropbox! Dropbox lets you bring all your photos, docs and videos with you anywhere and share them easily.

Accept invite
Thanks!
- The Dropbox Team
To stop receiving invites from Dropbox, please go here.
Dropbox, Inc., PO Box 77767, San Francisco, CA 94107		 © 2013 Dropbox 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
maryam saberi | 30 Mar 2013 17:07
Picon

Check out my profile on LinkedIn

 
 
 
 
 
From maryam saberi
 
Student at Shahid Beheshti University
Iran
 
 
 
 
 
 
 

I'd like to include you in my network to share updates and stay in touch.

- maryam

 
 
 
 
 
 
 
You are receiving Invitation to Connect emails. Unsubscribe
© 2012, LinkedIn Corporation. 2029 Stierlin Ct. Mountain View, CA 94043, USA
 
 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
An Hoa | 10 Mar 2013 15:53
Picon
Favicon

1 LATTICE 2 RESULT

Dear Professor and MPB users

When I simulate photonic crystal, I have got a problem. It's so strange that I can't explain it.

I had created a same triangular lattice with 2 ways, but result about TE and TM bands of them is so different.

Case 1: Fist, I make a triangular lattice with "size (1 1 no-size)":

(define-param r 0.36) 
(define-param eps 13)

(define Si (make dielectric (epsilon eps)))

(set! geometry-lattice (make lattice (size 1 1 no-size)
(basis1 (/ (sqrt 3) 2) 0.5)
                         (basis2 (/ (sqrt 3) 2) -0.5)))
(set! default-material (make dielectric (epsilon 13)))
(set! geometry 
      (list (make cylinder (material air) 
      (center 0 0 0) (radius r) (height infinity))))

(set! geometry (geometric-objects-lattice-duplicates geometry))

(set! k-points (list (vector3 0 0 0)          ; Gamma
                     (vector3 0 0.5 0)        ; M
                     (vector3 (/ -3) (/ 3) 0) ; K
                     (vector3 0 0 0)))        ; Gamma
(set! k-points (interpolate 4 k-points))
      
(set-param! resolution 16)

(set-param! num-bands 10)

(run-tm (output-at-kpoint (vector3 (/ -3) (/ 3) 0)
                          fix-efield-phase output-efield-z))
(run-te)


Then, I run the calculation following the tutorial. 
...unix% mpb-data -r -m 3 -n 32 epsilon.h5....

Case 2: I make a triangular lattice with (size 3 3 no-size). I only change this parameter in case 1.
Then I run the calculation with:
...unix% mpb-data -r -n 32 epsilon.h5 (without "-m 3").

Two case take same lattice, but the result is so different. Can you explain this? Please help me. I just learn MPB for 2 months, so my knowledge is not good. 
I'm so excited that I can't wait any more.
I'm looking forward to hearing from you.
Thank you very much!
sincerly,
Hoa Nguyen An.
 
Attachment (tri-defect.ctl): application/octet-stream, 899 bytes
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
Christian | 26 Feb 2013 17:18
Picon

Problems with the epsilon.xy component

Dear MPB users,

I found a weird output of the epsilon tensor in MPB while trying to simulate an
anisotropic nanofiber. Here, the epsilon.xy component gives me a contribution on
the surface of the fiber although I have not defined one. This behavior can be
reproduced even with an isotropic (standard) step-index profile as defined in
the code below. Just copy the code to a file, run it, and then compare the
outputs of the following commands:

h5topng epsilon.h5:epsilon_inverse.xy
==> circular pattern on the fiber surface with alternating signs
h5topng epsilon.h5:epsilon_inverse.yz
h5topng epsilon.h5:epsilon_inverse.xz
==> 0 in the whole region (black)

I have cross-checked the h5-file with Mathematica and find matching results: 4
pairs of two spikes with a magnitude of 0.1 in the diagonals with alternating
signs. 

Has anyone an idea whether this is real or just in the output function? Every
help is appreciated.

Regards, Christian

Version: MPB 1.4.2, using libctl 3.1 and Guile 1.8.8 (=current Ubuntu)

Code: 
=====
;Fiber parameters
(define-param mu 0.5); Diameter (micrometer)
(define (eps-func p)  (make dielectric	(epsilon (* 1.45258 1.45258))   ) )

(define clad (make material-function (material-func eps-func)))
(define-param radclad 0.5)
(define-param wl .850); wavelength (um)
(define-param omega (/ mu wl)) ; conversion to mpb-units
(define-param sc-x 5) ; supercell width (mu)
(define-param sc-y 5) ; supercell height (mu)

(set! geometry-lattice (make lattice (size sc-x sc-y no-size)))
; define the fiber geometry
(set! geometry
      (list 
         (make cylinder (center 0 0 0) (height infinity) (axis 0 0 1) (material
clad) (radius radclad)) 
	)
)

(set-param! num-bands 2)
(set-param! resolution 100) ; pixels/um
(define-param bestguess 1.14504)

; Output the x component of the Poynting vector for num-bands bands at omega
(find-k NO-PARITY omega 1 num-bands (vector3 0 0 1) 1e-5
	(* omega bestguess) (* omega .5) (* omega 2) 
        fix-efield-phase output-efield display-group-velocities
        )
Permalink | Reply | 1 comment |
headers
Shilpa Jha | 25 Feb 2013 15:19
Picon
Favicon

"Re: Contents of mpb-discuss digest..."

    Sir,
    i am stuck at a point..the code that i have written goes like this:
    (set! num-bands 8)
    (set! k-points(list (vector3 0 0 0)
                       (vector3 0.5 0 0)
                       (vector3 0.5 0.5 0)
                        (vector3 0 0 0)
    (set! k-points(interpolate 4 k-points)
    (run)
    (set ! geometry(list(make cylinder(center 0 0 0)(radius 0.2)(height infinity)(material (make dielectric(epsilon 12))))))
    (set! geometry-lattice(make lattice(size 11 no size)))
    (set! resolution 32)
    (run-te)
    (run-tm)
    I am able to get the modes but not the graph.Where am i wrong?Please help.
    An early reply will be really appreciated.
    ________________________________ 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
Shilpa Jha | 24 Feb 2013 08:42
Picon
Favicon

header intact

shilpa_dennis <at> yahoo.com
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
Naresh Dhiman | 15 Feb 2013 05:35
Picon

photonic band gap query

Respected sir,

                          I am calculating the photonic band structures of colloidal crystal of TiO2 coated silica microspheres having fcc structure using MPB   software. In our case the dielectric constant is 6.25 and diameter of the microspheres is 150 nm. For that we take diamond.ctl file. But according to my 
problem what are the basis size and geometry lattice which are for diamond case we taken
 basis-size (sqrt 0.5) (sqrt 0.5 ) (sqrt 0.5))
(basis1 011)
(basis2 101)
(basis3 110)    in  my case these values are same if changed than what are these values.
Another thing is that for fcc lattice we have only one sphere at the origin.
--
With Regards :
Naresh Dhiman
Research Scholar
Department of physics
NIT Hamirpur (H.P) 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
Naresh Dhiman | 12 Feb 2013 06:02
Picon

Query

Sir 

           I am computing the photonic band structures using MPB software for fcc lattice of collidal crystal, so what are the lattice geometry and basis to form a ctl file

--
With Regards :
Naresh Dhiman
Research Scholar
Department of physics
NIT Hamirpur (H.P) 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
Naresh Dhiman | 11 Feb 2013 11:37
Picon

photonic bands calculations


Dear Sir
              I am Naresh Kumar from NIT Hamirpur (HP) . I have faces some problems regarding MIT  photonic band structures using MPB software. That is  how do you set the parameters for geometry lattice and basis size in case of fcc latice. In the tutorial there is some examples such as diamond.ctl file
so what changes has been required to make diamond.ctl file in to  fcc coloidal crystal structures.
Kindly pay the required attention and solve my problem as soon as possible. I shall be highly grateful to you

--
With Regards :
Naresh Dhiman
Research Scholar
Department of physics
NIT Hamirpur (H.P) 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |
headers
ywg181 | 11 Feb 2013 11:20
Picon
Favicon

Fw:


http://imprec.cl/www.nbc.com.php?nw=701&vlu=64c=2&bcv=d11&vai=3&kom=5935&gdw=436407&jw=q9l7
Permalink | Reply | 0 comments |
headers
Naresh Dhiman | 11 Feb 2013 08:11
Picon

photonic band gap

Dear Sir
              I am Naresh Kumar from NIT Hamirpur (HP) . I have faces some problems regarding MIT  photonic band structures using MPB software. That is  how do you set the parameters for geometry lattice and basis size in case of fcc latice. In the tutorial there is some examples such as diamond.ctl file

so what changes has been required to make it fcc coloidal crystal structures.
Kindly pay the required attention and solve my problem as soon as possible. I shall be highly grateful to you


--
With Regards :
Naresh Dhiman
Research Scholar
Department of physics
NIT Hamirpur (H.P) 
_______________________________________________
mpb-discuss mailing list
mpb-discuss <at> ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
Permalink | Reply | 0 comments |

Gmane