The easiest way to project the slab modes for a line defect is just to use a large supercell with no defect.
On Thu, 15 Nov 2007, Ryan Hao wrote: > Dear Prof.Steven and others, > Thank you for your answer. > But my question is how to set the K path in calculating and > projecting the slab mode? > You known, projecting the slab mode needs to scan the full area > of Brillouin zone, then project to the waveguide direction. > > > Below is my code, Could you please have a look and tell me whether it > is correct or not (I think there may something wrong in setting the > reciprocal lattice and k path ): > (define-param kymin 0) > (define-param kymax 0.57735) > (define-param k-interp 20) > (define (do-stuff k k-hi k-inc) > (if (<= k k-hi) > (begin > > (set! k-points (interpolate k-interp (list (lattice->reciprocal > (vector3 k kymin 0)) > (lattice->reciprocal (vector3 k kymax 0))))) > (run-zeven ) > (do-stuff (+ k k-inc) k-hi k-inc) > ))) > (do-stuff 0 0.5 0.1) > > > Best wishes > Ryan > > > On Mar 28, 2007 2:20 AM, Steven G. Johnson <[EMAIL PROTECTED]> wrote: >> On Tue, 13 Mar 2007, Ryan Hao wrote: >>> In the case of line defect waveguide in photonic crystal slab,I succeed >>> in caculating the waveguide mode with MPB.but there still something >>> left:I must find way to project the band strucure of the regular lattice >>> of the slab(slab mode) and the lightcone?You can see in the below >>> picture,the blue line represent for the lightcone,and the green line >>> represent for slab mode. >> >> Projecting the light cone (for a uniform substrate/superstrate) is easy -- >> it is just the kmag output column divided by the substrate index. >> >> For projecting the modes of the unperturbed slab, the easiest thing to do >> is to use the same computational cell as your line-defect waveguide, but >> without the defect. (In fact, you can use a smaller supercell if you >> want, as long as you plot the slab bands for several values of ky from 0 >> to 0.5, where y is the direction perpendicular to your waveguide, assuming >> a rectilinear supercell.) >> >> Cordially, >> Steven G. Johnson >> >> _______________________________________________ >> mpb-discuss mailing list >> mpb-discuss@ab-initio.mit.edu >> http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss >> > > > > -- > =========================================== > > Best wishes > > Yours, > Ryan Hao > > _______________________________________________ > mpb-discuss mailing list > mpb-discuss@ab-initio.mit.edu > http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss > _______________________________________________ mpb-discuss mailing list mpb-discuss@ab-initio.mit.edu http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
