reply to arbitrary epsilon function. I had the same problem. you can first find the omega_n and Omega, sigma_n, and Gama_n from your data or plot. then, check it with matlab (use the same equation as it is written in MIT-material introduction for Lorentz and Drud model). afterward, you can use the result in meep. for me it gave good results. Best Mahdieh
--- On Wed, 10/6/10, [email protected] <[email protected]> wrote: From: [email protected] <[email protected]> Subject: meep-discuss Digest, Vol 56, Issue 6 To: [email protected] Date: Wednesday, October 6, 2010, 7:30 PM Send meep-discuss mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of meep-discuss digest..." Today's Topics: 1. Re: Arbitrary \epsilon distributions? (Arthur Thijssen) 2. Re: Arbitrary \epsilon distributions? (Arthur Thijssen) 3. How to efficiently obtain steady state response? (Lingyun Wang) ---------------------------------------------------------------------- Message: 1 Date: Wed, 6 Oct 2010 03:10:03 +0100 From: Arthur Thijssen <[email protected]> Subject: Re: [Meep-discuss] Arbitrary \epsilon distributions? To: Marco Zocca <[email protected]> Cc: "[email protected]" <[email protected]> Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Hi Marco, As far as I'm aware of, such a tool does not exist. But maybe some of the other users have been very busy. As for point two, I'm not a developer, so I don't know what's in the pipeline. The structure classes, using the scheme interface, are not implemented in MEEP itself, they are implemented using libctl. If you look at the utils folder in the libctl directory you'll find the source code. Adding a new geometric object would involve coding some c++ and Scheme, but the code for the current structures can be guide. An alternative would be using the c++ interface where you have more control on how you define your structure (you'll need to define a function that describes your structure), however the sub pixel averaging in the c-interface is not as accurate / fast as the one used in the Scheme interface. Good luck, Arthur On 5 October 2010 15:40, Marco Zocca <[email protected]> wrote: > Hello everyone, > > 1) I was wondering whether a tool or a hack exists to import arbitrary > permittivity distributions in MEEP, for example b/w bitmaps defining the > structure, or some type of implicit geometry definition like a CAD file or > the like. > > 2) To the developers : are new geometrical entities being planned for > implementation? E.g. more general shapes such as b-splines. > If this is not the case, how hard would it be to implement such a class? > > Thank you in advance and kindest regards, > > Marco Zocca > Dept. of Photonics Engineering > Technical Univ. of Denmark > > _______________________________________________ > meep-discuss mailing list > [email protected] > http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ab-initio.mit.edu/pipermail/meep-discuss/attachments/20101006/dc1ae1cb/attachment.html> ------------------------------ Message: 2 Date: Wed, 6 Oct 2010 03:10:03 +0100 From: Arthur Thijssen <[email protected]> Subject: Re: [Meep-discuss] Arbitrary \epsilon distributions? To: Marco Zocca <[email protected]> Cc: "[email protected]" <[email protected]> Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Hi Marco, As far as I'm aware of, such a tool does not exist. But maybe some of the other users have been very busy. As for point two, I'm not a developer, so I don't know what's in the pipeline. The structure classes, using the scheme interface, are not implemented in MEEP itself, they are implemented using libctl. If you look at the utils folder in the libctl directory you'll find the source code. Adding a new geometric object would involve coding some c++ and Scheme, but the code for the current structures can be guide. An alternative would be using the c++ interface where you have more control on how you define your structure (you'll need to define a function that describes your structure), however the sub pixel averaging in the c-interface is not as accurate / fast as the one used in the Scheme interface. Good luck, Arthur On 5 October 2010 15:40, Marco Zocca <[email protected]> wrote: > Hello everyone, > > 1) I was wondering whether a tool or a hack exists to import arbitrary > permittivity distributions in MEEP, for example b/w bitmaps defining the > structure, or some type of implicit geometry definition like a CAD file or > the like. > > 2) To the developers : are new geometrical entities being planned for > implementation? E.g. more general shapes such as b-splines. > If this is not the case, how hard would it be to implement such a class? > > Thank you in advance and kindest regards, > > Marco Zocca > Dept. of Photonics Engineering > Technical Univ. of Denmark > > _______________________________________________ > meep-discuss mailing list > [email protected] > http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ab-initio.mit.edu/pipermail/meep-discuss/attachments/20101006/dc1ae1cb/attachment-0002.htm> ------------------------------ Message: 3 Date: Wed, 6 Oct 2010 02:10:41 -0500 From: "Lingyun Wang" <[email protected]> Subject: [Meep-discuss] How to efficiently obtain steady state response? To: <[email protected]> Message-ID: <5f44833c52f2490cadb64b673eb89...@lwhp> Content-Type: text/plain; charset="iso-8859-1" Dear Steven and Meep users, I met a problem of obainning the steady state response of a cw source. For 2D case, since the data storage size is relatively small, I used the method that Steven suggested. Quote from Steven: (To others on this list: "steady-state" response is the usual term for the exp(-iwt) response field from an exp(-iwt) source, after all transients have died away.) To get the steady-state response from a CW source, currently the best way is to simply run for a long time after smoothly turning on a source (you will want to set the fwidth or width parameter of the continuous-src to make it turn on smoothly instead of suddenly). End of Quote. http://www.mail-archive.com/[email protected]/msg00040.html For example, my strucutre is 2D complex geometry. CW locates at the -x side and wave proprogates to +x side. I want to obtain the steady state response at certain x point along y direction. I just record the time response after turning on CW source for a long time for several period at the end of the running steps into a big hdf5 file. I assume wavefront in y direction having relatively uniform phase. After loading the file into matlab, and find out the maximum value for each postion point. That is how I find out the steady state. The problem now, is, for 3D, this hdf5 is really large and unrealistic to process in matlab. Is there any easier way to solve it efficiently? One way as indicated by Steven is to find out the time point where J term has zero phase by counting integer number of periods, and record the field at that time point. For period counting method, it can only garantee the zero phase at the source. But for abitrary location, this might not be true, since the phase also changes as function of position. How to find the zero phase for arbitrary position? Hope some one can give me some guidance. Thank you. ? Lingyun -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ab-initio.mit.edu/pipermail/meep-discuss/attachments/20101006/671cfeca/attachment-0001.htm> ------------------------------ _______________________________________________ meep-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss End of meep-discuss Digest, Vol 56, Issue 6 *******************************************
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