Thank you very much! Great! Em seg, 19 de out de 2020 12:28, Alexander Cerjan <alexcer...@gmail.com> escreveu:
> If you are interested in studying the types of PT structures which possess > patterned no-loss --- loss regions, which are typically what is studied > experimentally, using a conductivity to introduce your (spatially > inhomogeneous) loss is a good way to go. However, if you really do want to > use gain in your system, the only way to do this is using saturable gain, > https://meep.readthedocs.io/en/latest/Materials/#saturable-gain-and-absorption, > which corresponds to a slightly more complicated model for the gain than > what is typically considered in the PT literature, as it includes > non-linear saturation of the gain medium. You might be wondering why you > can't just add "eps - 1i*gain" type of linear dielectric to your system in > Meep, but the reason is that such a term will always lead to diverging > fields in a time-domain simulation, the non-linear saturation present in > the saturable gain model prohibits this, and also corresponds to what > happens in physical systems. If you use saturable gain, you can alternate > with regions of saturable loss to maintain PT of your passive structure. > > On Mon, Oct 19, 2020 at 8:48 AM Cícero Julião <juliaojun...@gmail.com> > wrote: > >> Thank you very much for your reply. However, perhaps I should explain my >> question better. >> >> I was working on using a Gaussian pulse as a source. >> I used a Gaussian font with a very short df, but there were still a lot >> of resonances. >> Then I thought of a continuous wave, so there would be only one frequency >> for analysis. >> But then the unwanted frequencies produced by the nature of the >> continuous wave appear. >> I didn't know what to do. >> >> If someone has already simulated material with PT symmetry and can >> provide some help, it would be wonderful. >> >> >> >> ---------- Forwarded message --------- >> De: Patrick Flanigan <flani...@etaphase.com> >> Date: seg., 19 de out. de 2020 às 01:54 >> Subject: Re: [Meep-discuss] pt symmetry >> To: Cícero Julião <juliaojun...@gmail.com> >> Cc: <meep-discuss@ab-initio.mit.edu> >> >> >> This might help: >> https://meep.readthedocs.io/en/latest/Materials/#conductivity-and-complex >> >> On Sun, Oct 18, 2020 at 12:23 PM Cícero Julião <juliaojun...@gmail.com> >> wrote: >> >>> Dear friends, >>> >>> I'm trying to write a code to simulate material with PT symmetry. But >>> I'm not sure how to include gain and loss in the dielectric constant. >>> >>> For example, can we use the material library to modulate material gain >>> and loss? Or is it necessary to write the epsilon function by hand? >>> >>> Thank you very much to all. >>> >>> >>> >>> -- >>> >>> Cícero Julião da Silva Junior >>> ____________________________________ >>> Instituto Federal de Alagoas - IFAL >>> Campus Murici >>> http://www.ifal.edu.br/ >>> _______________________________________________ >>> meep-discuss mailing list >>> meep-discuss@ab-initio.mit.edu >>> http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss >> >> >> >> -- >> Patrick Flanigan >> Etaphase, Inc. >> 8201 NE 164th Avenue, Suite 200 >> Redmond, WA 98052 >> http://etaphase.com/ >> >> >> -- >> >> Cícero Julião da Silva Junior >> ____________________________________ >> Instituto Federal de Alagoas - IFAL >> Campus Murici >> http://www.ifal.edu.br/ >> _______________________________________________ >> meep-discuss mailing list >> meep-discuss@ab-initio.mit.edu >> http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss > >
_______________________________________________ meep-discuss mailing list meep-discuss@ab-initio.mit.edu http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
