tidy3d.Graphene

class Graphene

Parametric surface conductivity model for graphene.

Parameters:

• mu_c (float = 0) – [units = eV]. Chemical potential in eV.

• temp (float = 300) – [units = K]. Temperature in K.

• gamma (float = 0.00041) – [units = eV]. Scattering rate in eV. Must be small compared to the optical frequency.

• scaling (float = 1) – Scaling factor used to model multiple layers of graphene.

• include_interband (bool = True) – Include interband terms, relevant at high frequency (IR). Otherwise, the intraband terms only give a simpler Drude-type model relevant only at low frequency (THz).

• interband_fit_freq_nodes (Optional[List[Tuple[float, float]]] = None) – Frequency nodes for fitting interband term. Each pair of nodes in the list corresponds to a single Pade approximant of order (1, 2), which is optimized to minimize the error at these two frequencies. The default behavior is to fit a first approximant at one very low frequency and one very high frequency, and to fit a second approximant in the vicinity of the interband feature. This default behavior works for a wide range of frequencies; consider changing the nodes to obtain a better fit for a narrow-band simulation.

• interband_fit_num_iters (NonNegativeInt = 100) – Number of iterations for optimizing each Pade approximant when fitting the interband term. Making this larger might give a better fit at the cost of decreased stability in the fitting algorithm.

Note

The model contains intraband and interband terms, as described in:

George W. Hanson, "Dyadic Green's Functions for an Anisotropic,
Non-Local Model of Biased Graphene," IEEE Trans. Antennas Propag.
56, 3, 747-757 (2008).

Example

>>> graphene_medium = Graphene(mu_c = 0.2).medium

__init__(**kwargs)

Init method, includes post-init validators.

Methods

__init__(**kwargs)	Init method, includes post-init validators.
add_type_field()	Automatically place "type" field with model name in the model field dictionary.
construct([_fields_set])	Creates a new model setting __dict__ and __fields_set__ from trusted or pre-validated data.
copy(**kwargs)	Copy a Tidy3dBaseModel.
dict(*[, include, exclude, by_alias, ...])	Generate a dictionary representation of the model, optionally specifying which fields to include or exclude.
dict_from_file(fname[, group_path])	Loads a dictionary containing the model from a .yaml, .json, .hdf5, or .hdf5.gz file.
dict_from_hdf5(fname[, group_path, ...])	Loads a dictionary containing the model contents from a .hdf5 file.
dict_from_hdf5_gz(fname[, group_path, ...])	Loads a dictionary containing the model contents from a .hdf5.gz file.
dict_from_json(fname)	Load dictionary of the model from a .json file.
dict_from_yaml(fname)	Load dictionary of the model from a .yaml file.
from_file(fname[, group_path])	Loads a Tidy3dBaseModel from .yaml, .json, .hdf5, or .hdf5.gz file.
from_hdf5(fname[, group_path, custom_decoders])	Loads Tidy3dBaseModel instance to .hdf5 file.
from_hdf5_gz(fname[, group_path, ...])	Loads Tidy3dBaseModel instance to .hdf5.gz file.
from_json(fname, **parse_obj_kwargs)	Load a Tidy3dBaseModel from .json file.
from_orm(obj)
from_yaml(fname, **parse_obj_kwargs)	Loads Tidy3dBaseModel from .yaml file.
generate_docstring()	Generates a docstring for a Tidy3D mode and saves it to the __doc__ of the class.
get_sub_model(group_path, model_dict)	Get the sub model for a given group path.
get_submodels_by_hash()	Return a dictionary of this object's sub-models indexed by their hash values.
get_tuple_group_name(index)	Get the group name of a tuple element.
get_tuple_index(key_name)	Get the index into the tuple based on its group name.
help([methods])	Prints message describing the fields and methods of a Tidy3dBaseModel.
interband_conductivity(freqs)	Numerically integrate interband term.
json(*[, include, exclude, by_alias, ...])	Generate a JSON representation of the model, include and exclude arguments as per dict().
numerical_conductivity(freqs)	Numerically calculate the conductivity.
parse_file(path, *[, content_type, ...])
parse_obj(obj)
parse_raw(b, *[, content_type, encoding, ...])
schema([by_alias, ref_template])
schema_json(*[, by_alias, ref_template])
to_file(fname)	Exports Tidy3dBaseModel instance to .yaml, .json, or .hdf5 file
to_hdf5(fname[, custom_encoders])	Exports Tidy3dBaseModel instance to .hdf5 file.
to_hdf5_gz(fname[, custom_encoders])	Exports Tidy3dBaseModel instance to .hdf5.gz file.
to_json(fname)	Exports Tidy3dBaseModel instance to .json file
to_yaml(fname)	Exports Tidy3dBaseModel instance to .yaml file.
tuple_to_dict(tuple_values)	How we generate a dictionary mapping new keys to tuple values for hdf5.
update_forward_refs(**localns)	Try to update ForwardRefs on fields based on this Model, globalns and localns.
updated_copy(**kwargs)	Make copy of a component instance with **kwargs indicating updated field values.
validate(value)

Attributes

interband_pole_residue	A pole-residue model for the interband term of graphene.
intraband_drude	A Drude-type model for the intraband term of graphene.
medium	Surface conductivity model for graphene.
mu_c
temp
gamma
scaling
include_interband
interband_fit_freq_nodes
interband_fit_num_iters

mu_c

temp

gamma

scaling

include_interband

interband_fit_freq_nodes

interband_fit_num_iters

property medium

Surface conductivity model for graphene.

property intraband_drude

A Drude-type model for the intraband term of graphene.

Returns:

A Drude-type model for the intraband term of graphene.

Return type:

Drude

property interband_pole_residue

A pole-residue model for the interband term of graphene. Note that this does not include the intraband term, which is added in separately.

Returns:

A pole-residue model for the interband term of graphene.

Return type:

PoleResidue

numerical_conductivity(freqs)

Numerically calculate the conductivity. If this differs from the conductivity of the Medium2D, it is due to error while fitting the interband term, and you may try values of interband_fit_freq_nodes different from its default (calculated) value.

Parameters:

freqs (List[float]) – The list of frequencies.

Returns:

The list of corresponding conductivities, in S.

Return type:

List[complex]

interband_conductivity(freqs)

Numerically integrate interband term.

Parameters:

freqs (List[float]) – The list of frequencies.

Returns:

The list of corresponding interband conductivities, in S.

Return type:

List[complex]

__hash__()

Hash method.