Hello everybody!
I'm trying to perform simulations in order to obtain the nonlinear response
of a given geometry. Currently, I'm "stretching muscles" by using the
*mie.py* example code given in the documentation. Over this code I'm adding
some lines in order to obtain the nonlinear response.
Hello everybody!
I am trying to find the dispersion function [image: D], typically measured
in ps/nm-km, of a simple SOI-waveguide. Silicon
waveguide is typically ranged in a few hundreds of nanometers. I am using
the k_find class from MPB, and then I perform derivative twice in order to
obtain
Thanks vare much for answering
El lun., 19 de oct. de 2020 16:11, Steven G. Johnson
escribió:
> If you just want the guided modes, I would tend to use MPB for this. It
> will give you the modal profile and the dispersion relation ω(β) (from
> which you can compute the effective index and
If you just want the guided modes, I would tend to use MPB for this. It will
give you the modal profile and the dispersion relation ω(β) (from which you can
compute the effective index and anything else)
> On Oct 19, 2020, at 11:44 AM, Alfredo Daniel Sánchez
> wrote:
>
> Dear friends and
Dear friends and colleges,
I'm trying to write a code to simulate the TE and TM modes in a kind
waveguide SOI. The structure of this waveguide is similar to that shown in
https://meep.readthedocs.io/en/latest/Python_Tutorials/Custom_Source/,
where we have several materials with different
as best i can tell, you've set the dimension of your structure to 3, but
the size in the x and y directions to be a single pixel. This is, depending
on what you're trying to do, a somewhat odd situation, because you have no
absorbing boundary condition in the x-y plane, only for waves which are
Dear Cerjan, thank you for your kind help.
Now let me summarize my tests. Firstly, I decreased sigma to 1e-100. However
the electric field still grows fast to infinity. My test results show that
sigma=1e-120 made the calculation converge. But why sigma is required so small.
It does not make
Thank you for your kind help.
Actually, I have tried the strength parameter sigma as small as 1e-20. But the
field rises to infinity rapidly. sigma can be used to tune the gain, can't it?
--
发自我的网易邮箱平板适配版
在 2020-07-26 04:47:29，"Alexander Cerjan" 写道：
This is likely the physically
This is likely the physically expected behavior. If your gain is coupling
to a mode of your system whose loss rate is less than that of the rate of
stimulated emission, your system will begin to lase, i.e. the field will
begin to grow exponentially. In real, physical systems, this is then
I am trying to use dispersive complex epsilon to describe gain in my
calculation. The parameters for the epsilon is defined as follows.
freq_32 = 2# emission frequency (units of 2\pi c/a)
gamma_32 = 0.306# FWHM emission linewidth in sec^-1 (units of 2\pi c/a)
sigma_32 = 1e-4
Hello, I'm modeling light propagation/scattering in biological cells. I've been
using MEEP for a while and feel like I have an OK handle on the pieces I've
been using. I am using the c++ libraries with my own code (the libraries I'm
using aren't current, if that turns out to be important).
You can use the default_material parameter of the Simulation object, for
example.
> On Jun 19, 2020, at 2:29 PM, Siwei Zeng wrote:
>
> Hi,
>
> I am a new player in Meep. Recently I try to simulate the transmission of
> silicon nitride directional coupler. The waveguide core material I use is
Hi,
I am a new player in Meep. Recently I try to simulate the transmission of
silicon nitride directional coupler. The waveguide core material I use is
silicon nitride. The waveguide cladding material is silicon dioxide. I have
checked the directional coupler example(
Hello all,
I'm currently using MPB for PBG calculation. I want to know whether there is a
way to import material with epsilon as a function of frequency? I think that
will improve the accuracy of the location of PBG. Thank you!
Best regards,
Qixiang
Dear Meep users and developers
I have a question concerning the interface of Medium transform(M [ Matrix class
]). In my present work, I need to model the anisotropic dielectric constant of
liquid crystals. Now, I calculate epsilon_diag=(a,b,c) and
epsilon_offdiag=(u,v,w) for the particular
Hi,
I have a simple question. Is the a conversion between SI and meep units for
permittivity and permeability or are they the same in meep units?
Best,
Daniel Heligman
___
meep-discuss mailing list
meep-discuss@ab-initio.mit.edu
Hi All,
I typically use h5topng on output field arrays and then use ffmpeg to
generate movies. What I would like to do is to offer the eps file as an
alpha overlay on the movies in a way that the channel could be turned on or
off while playing the movie.
In other words, if I make the ffmpeg
Dear Steven and meep users
Recently I tried to use meep to do calculation on nonlinear. But I’m confused
on the calculation of refractive index change caused by nonlinear. This note
(http://ab-initio.mit.edu/wiki/index.php/Units_and_nonlinearity_in_Meep) gives
some details about my
Dear Steven and meep users
Recently I tried to use meep to do calculation on nonlinear. But I’m confused
on the calculation of refractive index change caused by nonlinear. This note
(http://ab-initio.mit.edu/wiki/index.php/Units_and_nonlinearity_in_Meep) gives
some details about my
Hello Rui,
the only thing happens here is scaling the 4 Maxwell equations under the
condition that c0 = 1.
The solutions are not unique, you can choose the scaling method, which
is more suitable for your problem. (for example, you can let the
permittivity as the value in the real world, or keep
You get same result if you also scale geometry (slab thickness maybe)
Gursoy akguc
Sent from my iPad
On Jul 29, 2013, at 2:33 AM, Rui La larui...@gmail.com wrote:
Hi meep users,
I am new to meep and have some questions about units and sizes in the code of
meep.
I want to measure the
Responding to my own question: The code below (posted on a forum somewhere)
works on MEEP version 1.1.1.
(reset-meep)
(set! dimensions 2)
(set! force-complex-fields? true)
(set! geometry-lattice (make lattice (size 12 12 no-size) )) ;
computational domain
(set! sources (list (make source (src
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA256
Hello Eric,
In Meep 1.2 you have to patch the norm2() function in CG method to let the
solve-cw work.
Chuanren
Eric Smoll ericsm...@gmail.com schrieb:
Responding to my own question: The code below (posted on a forum
somewhere)
works on MEEP
Probably the easiest workaround is to use the field-integration code, which
works fine in MPI (unlike get-field-pt). Integrating over a volume of size 0
is equivalent to just evaluating the function at a point (since zero-size
dimensions in the integration volume are just interpolated, not
I used Ardavan Oskooi sample input file to form a moving current source
to generate Cerenkov radiation in photonic crystal lattice. The problem
is I am really struggling with Scheme syntax. I am trying to get the
frequencies of the emitted Hz radiation. So I am trying to use the
harminv
PENG WANG peng.wang@... writes:
Hello, Dear MEEP developers and users:
I am a new user of MEEP software. I currently installed MEEP in Ubuntu,
which is suggested by Professor Steve
as the best way to install MEEP.
But when I call meep from Matlab by:
unix('meep
Hello, steven
I'm now using MEEP,and I have some problems don't know how to do it. I
hope you can help me !
First, how to define my own source in meep ,I want to use the source
to send my own data ,rather than the data generated by suorce itself. I want ro
know how to load
Hello all,
I have searched the archives and read through all the material on the
website but am still unsatisfied with my understanding of units on the
Material Dispersion
page.
http://ab-initio.mit.edu/wiki/index.php/Meep_Tutorial/Material_dispersion
I know from the archives that omega and
Dear meep users and Dr. Steven Johnson,
I would like to see optical bistability in 1-D photonic crystal. therefore I
have
used a paper in this field,
http://www.sciencedirect.com/science/article/pii/S0030401802016899.
I defined a 1-D photonic crystal which consist of alternative
Dear Meep developers and users,
I am reading the online tutorial of banddiagram and seeing that the frequency
is normailized to a number without unit.
Supposing the unit length corresponds to 100nm, what's the actual freq of 0.5?
Does it mean f=0.5*c/100 and the angular freq=2*pi*0.5*c/100
Hello, Dear MEEP developers and users:
I am a new user of MEEP software. I currently installed MEEP in Ubuntu,
which is suggested by Professor Steve as the best way to install MEEP.
But when I call meep from Matlab by:
unix('meep test.ctl test.out')
The output file
Dear Peng,
have you tried to start meep not from matlab environment but from ubuntu's
shell which you prefer to use?
And have you installed meep from debian's repository or compiled it by
yourself?
BR,
Alexandr.
11 ноября 2011, 06:56 от PENG WANG peng.w...@utah.edu:
Hello, Dear MEEP
Hello, MEEP developers and users,
I am a greenhorn in MEEP software. I currently have a problem in creating
oblique incident plane-waves in periodic structures. Although I have read some
of the discussions in the mailing list, I still have some problems. The
following is the code I used as a
Dear meep users and Dr. Steven Johnson,
I'd like to know what kind of source we should use for calculating optical
bistability in nonlinear photonic crystals.
is it possible to use predefined source in meep like gaussian-src or not? and
if the answer is yes, how?
according to my information
Dear meep user and Dr. Steven Johnson,
All examples about transmission spectrum in meep tutorial explain how to
calculate
transmission in a frequency range. In other word the horizontal axis represents
a range
of frequencies and the vertical axis represents transmission.during this
Dear meep users and Dr. Steven Johnson,
I have two questions regarding the source in meep software,
1- What is the conception of turning on and especially turning off the source?
turning on the source , specifies the moment that the Gaussian pulse fully
formed and
turning off the
jack swagger jswagger65@... writes:
Dear MEEP users,
I am trying to model the Multilayered nanoshell, which
contains
a metal core, a dielectric silica and the outer metal shell. At 1st, i divide
this complex structure into several parts and calculate its extinction
Dear meep mpb users
In MPB user tutorial , when it;s described calculation of Photonic band
structure of triangular lattice,
we see such statement about k-point of irreducible Brillouin zone of a
triangular lattice.
(set! k-points (list (vector3 0 0 0) ; Gamma
Dear MEEP users,
I am trying to model the Multilayered nanoshell, which contains
a metal core, a dielectric silica and the outer metal shell. At 1st, i divide
this complex structure into several parts and calculate its extinction
efficiency. I know from the litrature that if you
Hi,
During past several days, I found something more about that bizarre problem
with meep-mpi. If meep-mpi is used without mpirun, that is, meep-mpi a.ctl,
then it can run successfully. However, if mpirun is involved, i.e., mpirun
-np 4 meep-mpi a.ctl, then the same problem (.ctl file cannot be
Thank you, Prof. Steven.
I've got some ideas about this problem: I see a small down movement of the
branch of
the dispersion diagram in the Kerr-nonlinear periodic structure. At this moment
with
(run-k-points...) method I just see this movement when the ampliude of the
signal is not big
Dear Prof. Steven and dear meep users.
I do appreciate if you can help me with understanding
such a easy thing in meep::
Can I use (run-k-points...) statement in my ctl-file
{e.g. (run-k-points 300 (interpolate k-interp (list (vector3 kmin) (vector3
kmax)}
if my dielectric is
On Nov 1, 2010, at 11:32 AM, Alexandr Sadovnikov wrote:
Dear Prof. Steven and dear meep users.
I do appreciate if you can help me with understanding
such a easy thing in meep::
Can I use (run-k-points...) statement in my ctl-file
{e.g. (run-k-points 300 (interpolate k-interp (list (vector3 kmin)
Thank you, Prof. Steven!
I just tried to compute band gap diagram for 2d periodical structure, with
nonlinear
layers and then I want to compare this result with the results from the
nonlinear Shroedinger equations.
So I want to see how the cut-off frequencies changes with the amplitude gets
On Nov 1, 2010, at 12:15 PM, Alexandr Sadovnikov wrote:
I just tried to compute band gap diagram for 2d periodical
structure, with nonlinear
layers and then I want to compare this result with the results from
the nonlinear Shroedinger equations.
This is a complicated question because it
Hello, dear Prof. Steven and Meep Users.
I would like to ask you about application and use of
meep to the computation of magnet systems such as
ferromagnetic films in which the magnetostatic waves can
propagate. So I'm going to do this computation (of magnetostatic
wave propagation) using
Dear Prof. Steven and Meep users:
I hope to repeat the work (),but I am not sure of the nonlinear
feedback parameter:
(1) |E.E|^2 VS |E.E^*|^2 : Since the field values stored in meep are
real, is there any difference between them?
(2) A single linear simulation is enough to determine its vavlue
Dear Feng,
try to output field components not only at the end of computation time
but e.g. for discrete time : try to use command at-every.
BR,
Alexandr.
___
meep-discuss mailing list
meep-discuss@ab-initio.mit.edu
On Nov 16, 2009, at 1:50 AM, 蒙自明 wrote:
Dear Steven and all:
I am a new user of Meep. What I want to ask is about:
How can I determine the time-average input power and record the
time-average output power at some position?
According to the part Units and Nonlinearity in Meep on the
Dear Steven and all:
I am a new user of Meep. What I want to ask is about:
How can I determine the time-average input power and record the
time-average output power at some position?
According to the part Units and Nonlinearity in Meep on the website, the
input power is approximately
Hi Steven,
Thanks a lot for helping me find out a big mistake I made - that is, I was
confused by the defination of current in MEEP, which is totally different
from that in driving circuit.
So here comes another question. I notice that in other FDTD softwares such
as XFDTD and SEMCAD,
(I don't see my reply posted, so I'm posting it again. I'm sorry if this
mail is duplicated.)
Hi Steven,
Thanks a lot for helping me find out a big mistake I made - that is, I was
confused by the defination of current in MEEP, which is totally different
from that in driving circuit.
So here
The current in Meep is added directly as a specified free current J in
Maxwell's equations (see Maxwell's equations in the Meep intro). Meep
does not simulate the driving force behind this free current, nor does
the current have to be placed in a conductor. Specifying a current
means
Hello everyone,
I'm trying to set a current source and find there's no parameter to
describe the resistance(50 ohm, normally) in the feeding point, which is
frequently used in EM emission system. That's quite strange. Can you tell me
why? Your earliest reply will be greatly appretiated.
hello anyone
I didn't understand from the reference how
to get a numerical value of the flux in area which I define
where to write this command?
I should see at the output numerical value?
___
meep-discuss mailing list
meep-discuss@ab-initio.mit.edu
Dear meep users and Dr. Johnson,
Our group is trying to do some calculation by meep-mpi with a computing
space of 300*300*300. The resolution is setting to 1.
We installed OpenMPI which is very easy to to use. But the calculation is
about 900s/step when we use 8 processors. We need 1500 steps to
according to your reply, here are a few calculations:
a=1 micrometer =1*10^-6 meter
resolution =1000
courant=.5
hence
dt=2000 a/c in meep units.
or
dt=2000*10^-6/(3*10^8)
=6.66*10^-11 seconds
is it correct?
Please look how Meep units are defined:
Hello!
I am trying to simulate em fields in the vicinity of nanoparticles.
parameters:
a = 1 micron
How do we find the size of the timestep in seconds?
How do we know how many wavelengths will pass at a particular point in two
timesteps?
Here the last part of the program:
(set!
How do we find the size of the timestep in seconds?
How do we know how many wavelengths will pass at a particular point in
two timesteps?
Hi,
timestep (dt) is set when you are define your structure and it depends
on two parameters: structure resolution r and Courant parameter (dt =
r/Courant,
Dear Steven and Meep users,
I am writing a ctl code to model a cone optical fiber tip with center
aperture (diameter 100nm) and ring gratings on the side wall of the Au
coating layer. So this is a perfect cylindrical symmetrical geometry.
The source wavelength is 405 nm with circular
Hello!
I am trying to calculate field energy in air before the field passes through
a medium and after it passes through. The medium has a refractive index of
2.1609.
I have used two cases: with periodic boundary conditions (using k-point) and
without it.
Also I have put metal nano cylinder and
*Hello!!
**I am trying to simulate the propogation of a plane wave in a glass of
refractive index 1.47.
But, the png image showed distortion of the plane wave with a bulge at the
center.
When I remove the pml layer in Y direction, I am able to get the plane wave
in the glass. But, by removing
Hi,
I want to simulation the respond of a waveguide to different pulses.
However, It takes time for the waveguide reach a stable status.
So I want to store the status and load it every time for different pulses.
It will save a lot of time.
I checked the source code. It seems the fields can be
Dear Dr.Steven and meep users,
I have a question of the command in-volume.
I am trying to take out the data using in-volume.
And I use a 2d-TM planewave as source.
(set! resolution 10)
(in-volume (volume (center 0 1 0) (size 2 0 0)) output-efield-z))
..
I got 22
On Jun 25, 2008, at 10:24 AM, mehdi miri wrote:
Hi there
Does the MPI (Parallel Processing) features work with Scheme
Scripting? (*.ctl files?)
Yes.
___
meep-discuss mailing list
meep-discuss@ab-initio.mit.edu
Hi Andreas, thanks for your quick response,
I would not think that you can make things worse by putting a small
pml
but I think a pml with less than 5 cells also makes no sense.
ok, I understand that such a small pml layer does not make much sense.
I didn't mean to make it that small, maybe
Alex,
My experience with plasmonic problems is that 2nm isn't fine enough of a
resolution. I only got nice results with 0.5nm (I had to use a
cluster). I was working with a Drude model for silver, not gold, but I
imagine that you will have similar results.
I don't think you can shave
Alexander Sprafke wrote:
Lets say I have a pml layer which is too thin. Do these reflections
come from propagating waves going through the pml layer and being
reflected at the end of the computational cell, going through the pml
layer again and entering the region of interest. Or is it the
Alex,
I did recently play with a similar problem, only at wavelengths in the
mid-infrared (3-5 µm), making the whole problem even worse. I can say that I do
get numerical reflections from PMLs even if they are 1 µm or so (I did not try
much bigger). Though in my case, that seem to be due to
Hi there
Does the MPI (Parallel Processing) features work with Scheme Scripting?
(*.ctl files?)
___
meep-discuss mailing list
meep-discuss@ab-initio.mit.edu
http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
Dear Alex,
You can decide which dataset extract with the command 'h5tovtk' using the
modifier -d followed by the name of the dataset.
By default extracts the first dataset that in your case is 'ex' (look at the
man page)
To extract 'Ey' dataset for instance:
h5tovtk -t 150 -o test.vtk -d ey
Dear Steven and meep community,
I created a hdf5-file with all E-field components using
...
(to-appended e (at-every 0.5 output-efield))
...
this seems to work, since h5ls gives:
h5ls test-e.h5
ex Dataset {50, 50, 50, 200/Inf}
ey Dataset {50, 50, 50,
On Jun 15, 2008, at 6:40 AM, Juntao Xi wrote:
Hi, Steven and Meepers,
As the following setting
-Resolution 100
-in volume (size 1 1.2 ) output-efield-y
The output datasets is 102*122.
Why is not it 100*120?
Meep adds a couple of extra pixels at the ends to implement the
boundary
Hi, meep users and Steven:
I try to figure how the cw-source turns on and off.
I use the parameters as below:
(define-param run_time 17 )
(src (make continuous-src (frequency fcen) (end-time (* run_time (/ 1
fcen))) (width (* 0.7 lam)) (cutoff (* 0.003 lam) )
I recorded the
On Thu, 18 Oct 2007, Gao Jie wrote:
I am interested in calculating local density of states in 2D photonic
crystal structure with/without defect cavities. Theoretically it requires
calculation of the green's functions G(r,w). I am wondering whether it can
be done in MEEP?
Yes. The Green's
Hi all,
It has worked now, thanks to the discussion with Zheng. I need to call
functions recognized by Guile, such as seed-random-state to set!
*random-state* in meep.
Best,
Roy
On 9/5/07, Zheng LI [EMAIL PROTECTED] wrote:
hi, Roy
i'm not familiar with your random procedure. however, if
Hi dear all meep users,
I have a question about calling the procedure (random module) in .ctl
file. I have expected different *random-state* for a number of runs of
my .ctl file, so I try to add the below line
(set! *random-state* (make-random-state #t)) ; to change the random-state
into my
Hi, everyone:
I referred to archives below and successfully established one triangular:
On Tue, 14 Nov 2006, Pascual Munoz Munoz wrote:
I've been looking to the 'loop' howto on the wiki, but I cannot manage
how to make a loop that makes a list of objects in different positions
and with
Hi everyone:
I refer to one of archives as below to build up the
object:
On Tue, 14 Nov 2006, Pascual Munoz Munoz wrote:
I've been looking to the 'loop' howto on the wiki,
but I cannot manage
how to make a loop that makes a list of objects in
On Wed, 13 Jun 2007, adrian wrote:
I have one question about PML. I ran one case with 2-D waveguide
structure consisting of three layers. I know the correct description for
PML is just to set the thickness of PML and meep will automatically put
it inside the computation cell. However,
Hi, everyone:
I have one question about PML. I ran one case
with 2-D waveguide structure consisting of three
layers. I know the correct description for PML
is just to set the thickness of PML and meep will
automatically put it inside the computation cell.
However, the result was not
Dear MEEP users,
I am trying to figure out the decaying function of gaussian-src or
continuous-src, and hope to hear your advice.
The default source end-time[] is infinity (never turn off) according to MEEP
reference.
And, the default cutoff[] is 3.0 and it is the number of widths the current
If you are familiar with Emacs， its Scheme-mode may help you debug the
codes by writing the following codes in your .emacs file:
(setq scheme-program-name meep)
(setq scheme-mit-dialect nil)
Best,
Zheng Li
On Sun, 2006-11-05 at 23:13 -0500, Ashifi wrote:
Thanks for the tip, Matt. I based my
I am sorry. I suggests it only because I am learning it now.
On the other hand, a missing ')' also invokes this kind of error
message.
Good luck,
Zheng Li
On Mon, 2006-11-06 at 11:13 -0500, Ashifi wrote:
Don't mean to start a VI vs Emacs war here, but is there anything like
this for VI? My
Hi
I have three questions.I get the result in dielectric structure. But I do not get the same result in metal-dielectricstructure compare to the text book. My questions areFirst, how to get the 2Dmetal-dielectric w-k diagram.
Second, 3Ddielectric-metal-dielectric slab structure w-k diagram.Third,
Dear Steven, 1. It seems that Meep does not support slab
structure with drude type metal. I got the result about 3D photonic
crystal (slab structure with the air hole) dispersion curve.
But, when I simulate the slab structure
(metal slab), the result is wrong. Could you give me some
86 matches
Mail list logo
