[Meep-discuss] epsilon-input-file format?

[Priscilla Kelly]

Hello MEEP Users,

I am trying to input a specialized complex permittivity using an HDF5 file using epsilon-input-file but I have run into problems with how the data needs to be represented. I have frequency data and permittivity data which I want to set the grid with.
This is what the file I made looks like: <HDF5 dataset "multilayered:dataset": shape (1000, 2), type "<c16">

I called it in my scheme file by using: (set! epsilon-input-file “multilayered.h5”)

I tried transposing the data, but I still get this error:

5 HDF5-DIAG: Error detected in HDF5 (1.10.1) thread 0:
6 #000: H5Dio.c line 171 in H5Dread(): can't read data
7 major: Dataset
8 minor: Read failed
9 #001: H5Dio.c line 416 in H5D__read(): unable to set up type info
10 major: Dataset
11 minor: Unable to initialize object
12 #002: H5Dio.c line 987 in H5D__typeinfo_init(): unable to convert between src and dest datatype
13 major: Dataset
14 minor: Feature is unsupported
15 #003: H5T.c line 4560 in H5T_path_find(): no appropriate function for conversion path
16 major: Datatype
17 minor: Unable to initialize object
18 read in 1000x2x1 epsilon-input-file “multilayered.h5"

What is the correct way to format the freq and associated perm data?

Thank you,
Priscilla

[Ardavan Oskooi]

Post by Priscilla Kelly
I am trying to input a specialized complex permittivity using an HDF5 file using epsilon-input-file but I have run into problems with how the data needs to be represented. I have frequency data and

Currently, only frequency-independent, real-valued permittivities can be
imported as an HDF5 file. In general, since Meep is a time-domain
solver, the only way to model frequency-dependent complex permittivites
is by fitting the data to a Drude-Lorentzian susceptibility profile
<http://meep.readthedocs.io/en/latest/Materials/#material-dispersion>.
Note that we recently added a materials library
<http://meep.readthedocs.io/en/latest/Materials/#materials-library> for
11 metals commonly used in optoelectronic devices. For narrowband or
frequency-independent calculations involving complex epsilon, you can
instead specify the conductivity
<http://meep.readthedocs.io/en/latest/Materials/#conductivity-and-complex>
(to speed up these kinds of calculations, you may want to consider using
Meep's frequency-domain solver
<http://meep.readthedocs.io/en/latest/Python_User_Interface/#frequency-domain-solver>).