# This code is part of KQCircuits
# Copyright (C) 2022 IQM Finland Oy
#
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import abc
import logging
from kqcircuits.elements.element import Element
from kqcircuits.pya_resolver import pya
from kqcircuits.simulations.simulation import Simulation, get_simulation_layer_by_name, to_1d_list
from kqcircuits.util.parameters import Param, pdt, add_parameters_from
[docs]
@add_parameters_from(Simulation, "name", "box", "extra_json_data")
class CrossSectionSimulation:
"""Class for co-planar waveguide cross-section simulations.
This class is intended to be subclassed by a specific simulation implementation; The subclass should implement the
method 'build' which defines the simulation geometry and material properties.
Layer names in cross-section geometry don't need to obey KQC default layers. The layers use following name coding:
- Layer name 'vacuum' is reserved for vacuum material. The vacuum layer can be left empty; then the empty space
inside the 'box' is automatically filled with vacuum.
- All layers that include word 'signal' are considered as signal metals. Different signal layers are considered as
separate signals so that the result matrices has row and column for each signal layer. The order of signals is the
same as where they are introduced by calling 'get_sim_layer' function.
- All layers that include word 'ground' are considered as ground metal.
- Any other layer is considered as dielectric. The permittivity can be set using the 'set_permittivity' function.
"""
LIBRARY_NAME = None # This is needed by some methods inherited from Element.
london_penetration_depth = Param(
pdt.TypeList,
"London penetration depth of metals",
0.0,
unit="m",
docstring="London penetration depth is implemented for one signal simulation only",
)
xsection_source_class = Param(
pdt.TypeNone,
"Simulation class XSection tool was used on",
None,
docstring="Class from which the simulation was generated using the XSection tool. Used to get the schema.",
)
ignore_process_layers = Param(pdt.TypeBoolean, "Ignores automatic function call of process_layers", False)
def __init__(self, layout, **kwargs):
"""Initialize a CrossSectionSimulation.
The initializer parses parameters, creates a top cell, and then calls `self.build` to create
the simulation geometry.
Args:
layout: the layout on which to create the simulation
Keyword arguments:
`**kwargs`:
Any parameter can be passed as a keyword argument.
"""
if layout is None or not isinstance(layout, pya.Layout):
error_text = "Cannot create simulation with invalid or nil layout."
error = ValueError(error_text)
logging.error(error_text)
raise error
self.layout = layout
schema = type(self).get_schema()
# Apply kwargs or default value
for parameter, item in schema.items():
if parameter in kwargs:
setattr(self, parameter, kwargs[parameter])
else:
setattr(self, parameter, item.default)
self.cell = kwargs["cell"] if "cell" in kwargs else layout.create_cell(self.name)
self.layer_dict = {}
self.permittivity_dict = {}
self.units = kwargs.get("units", "um")
self.build()
if not self.ignore_process_layers:
self.process_layers()
# Inherit specific methods from Element
get_schema = classmethod(Element.get_schema.__func__)
[docs]
@abc.abstractmethod
def build(self):
"""Build simulation geometry.
This method is to be overridden, and the overriding method should create the geometry to be simulated.
"""
return
[docs]
def process_layers(self):
"""Limit layers by self.box and create vacuum layer if it doesn't exist."""
bbox = pya.Region(self.box.to_itype(self.layout.dbu))
for layer in self.layer_dict.values():
shapes = self.cell.shapes(self.layout.layer(layer))
region = pya.Region(shapes) & bbox
shapes.clear()
shapes.insert(region)
if "vacuum" not in self.layer_dict:
vacuum = bbox.dup()
for v in self.layer_dict.values():
vacuum -= pya.Region(self.cell.shapes(self.layout.layer(v)))
self.cell.shapes(self.get_sim_layer("vacuum")).insert(vacuum)
[docs]
def register_cell_layers_as_sim_layers(self):
"""Takes all layers that contain any geometry and registers them as simulation layers
This method resets the internal simulation layer dictionary.
"""
self.layer_dict = {}
self.permittivity_dict = {}
for l in self.layout.layer_infos():
if len(list(self.cell.each_shape(self.layout.layer(l)))) > 0:
self.layer_dict[l.name] = l
[docs]
def get_sim_layer(self, layer_name):
"""Returns layer of given name. If layer doesn't exist, a new layer is created."""
if layer_name not in self.layer_dict:
layer_info = None
for l in self.layout.layer_infos():
if l.datatype == 0 and l.name == layer_name:
# If there is a layer with layer_name in layout (used by other cell), reuse that
layer_info = l
if layer_info is None:
layer_info = get_simulation_layer_by_name(layer_name)
self.layer_dict[layer_name] = layer_info
return self.layout.layer(self.layer_dict[layer_name])
[docs]
def set_permittivity(self, layer_name, permittivity):
"""Sets permittivity for layer of given name."""
self.permittivity_dict[layer_name] = permittivity
[docs]
def get_parameters(self):
"""Return dictionary with all parameters and their values."""
return {param: getattr(self, param) for param in (self.xsection_source_class or type(self)).get_schema()}
[docs]
def get_dict_by_layers(self, param_name):
"""Helper function to cast a parameter given as a list of same length as the face stack into
a dict of the format simulation_layer -> value"""
face_list = to_1d_list(self.face_stack) if hasattr(self, "face_stack") else [""]
data_list = to_1d_list(getattr(self, param_name))
num_faces = len(face_list)
if len(data_list) == 1 and num_faces > 1:
data_list = num_faces * [data_list[0]]
elif len(data_list) != num_faces:
logging.warning(f"Number of faces and {param_name} do not match ({num_faces} vs {len(data_list)})")
metal_layers = [n for n in self.layer_dict if "signal" in n or "ground" in n]
return {layer: v for face, v in zip(face_list, data_list) for layer in metal_layers if layer.startswith(face)}
[docs]
def get_layers(self):
return self.layer_dict.values()
[docs]
def get_simulation_data(self):
"""Return the simulation data in dictionary form.
Returns:
dictionary of relevant parameters for simulation
"""
simulation_data = {
"simulation_name": self.name,
"units": self.units,
"layers": {k: v.layer for k, v in self.layer_dict.items()},
"london_penetration_depth": self.get_dict_by_layers("london_penetration_depth"),
**{f"{k}_permittivity": v for k, v in self.permittivity_dict.items()},
}
return simulation_data