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tutorial updates

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This commit is contained in:
jan 2022-02-27 21:21:44 -08:00
parent 0471addd65
commit 47d655d270
4 changed files with 549 additions and 260 deletions
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48
examples/tutorial/basic.py → examples/tutorial/basic_shapes.py
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@ -4,12 +4,18 @@ import numpy
from numpy import pi
from masque import layer_t, Pattern, SubPattern, Label
from masque.shapes import Circle, Arc
from masque.shapes import Circle, Arc, Polygon
from masque.builder import Device, Port
from masque.library import Library, DeviceLibrary
import masque.file.gdsii
import pcgen
# Note that masque units are arbitrary, and are only given
# physical significance when writing to a file.
GDS_OPTS = {
'meters_per_unit': 1e-9, # GDS database unit, 1 nanometer
'logical_units_per_unit': 1e-3, # GDS display unit, 1 micron
}
def hole(
@ -20,8 +26,8 @@ def hole(
Generate a pattern containing a single circular hole.
Args:
layer: Layer to draw the circle on.
radius: Circle radius.
layer: Layer to draw the circle on.
Returns:
Pattern, named `'hole'`
@ -32,6 +38,32 @@ def hole(
return pat
def triangle(
radius: float,
layer: layer_t = (1, 0),
) -> Pattern:
"""
Generate a pattern containing a single triangular hole.
Args:
radius: Radius of circumscribed circle.
layer: Layer to draw the circle on.
Returns:
Pattern, named `'triangle'`
"""
vertices = numpy.array([
(numpy.cos( pi / 2), numpy.sin( pi / 2)),
(numpy.cos(pi + pi / 6), numpy.sin(pi + pi / 6)),
(numpy.cos( - pi / 6), numpy.sin( - pi / 6)),
]) * radius
pat = Pattern('triangle', shapes=[
Polygon(offset=(0, 0), layer=layer, vertices=vertices),
])
return pat
def smile(
radius: float,
layer: layer_t = (1, 0),
@ -66,14 +98,18 @@ def smile(
return pat
def _main() -> None:
def main() -> None:
hole_pat = hole(1000)
smile_pat = smile(1000)
tri_pat = triangle(1000)
masque.file.gdsii.writefile([hole_pat, smile_pat], 'basic.gds', 1e-9, 1e-3)
units_per_meter = 1e-9
units_per_display_unit = 1e-3
masque.file.gdsii.writefile([hole_pat, tri_pat, smile_pat], 'basic_shapes.gds', **GDS_OPTS)
smile_pat.visualize()
if __name__ == '__main__':
_main()
main()

368
examples/tutorial/devices.py Normal file
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@ -0,0 +1,368 @@
from typing import Tuple, Sequence, Dict
import numpy
from numpy import pi
from masque import layer_t, Pattern, SubPattern, Label
from masque.shapes import Polygon
from masque.builder import Device, Port
from masque.file.gdsii import writefile
from masque.utils import rotation_matrix_2d
import pcgen
import basic_shapes
from basic_shapes import GDS_OPTS
LATTICE_CONSTANT = 512
RADIUS = LATTICE_CONSTANT / 2 * 0.75
def perturbed_l3(
lattice_constant: float,
hole: Pattern,
trench_dose: float = 1.0,
trench_layer: layer_t = (1, 0),
shifts_a: Sequence[float] = (0.15, 0, 0.075),
shifts_r: Sequence[float] = (1.0, 1.0, 1.0),
xy_size: Tuple[int, int] = (10, 10),
perturbed_radius: float = 1.1,
trench_width: float = 1200,
) -> Device:
"""
Generate a `Device` representing a perturbed L3 cavity.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
trench_dose: Dose for the trenches. Default 1.0. (Hole dose is 1.0.)
trench_layer: Layer for the trenches, default `(1, 0)`.
shifts_a: passed to `pcgen.l3_shift`; specifies lattice constant
(1 - multiplicative factor) for shifting holes adjacent to
the defect (same row). Default `(0.15, 0, 0.075)` for first,
second, third holes.
shifts_r: passed to `pcgen.l3_shift`; specifies radius for perturbing
holes adjacent to the defect (same row). Default 1.0 for all holes.
Provided sequence should have same length as `shifts_a`.
xy_size: `(x, y)` number of mirror periods in each direction; total size is
`2 * n + 1` holes in each direction. Default (10, 10).
perturbed_radius: radius of holes perturbed to form an upwards-driected beam
(multiplicative factor). Default 1.1.
trench width: Width of the undercut trenches. Default 1200.
Returns:
`Device` object representing the L3 design.
"""
# Get hole positions and radii
xyr = pcgen.l3_shift_perturbed_defect(mirror_dims=xy_size,
perturbed_radius=perturbed_radius,
shifts_a=shifts_a,
shifts_r=shifts_r)
# Build L3 cavity, using references to the provided hole pattern
pat = Pattern(f'L3p-a{lattice_constant:g}rp{perturbed_radius:g}')
pat.subpatterns += [
SubPattern(hole, scale=r,
offset=(lattice_constant * x,
lattice_constant * y))
for x, y, r in xyr]
# Add rectangular undercut aids
min_xy, max_xy = pat.get_bounds_nonempty()
trench_dx = max_xy[0] - min_xy[0]
pat.shapes += [
Polygon.rect(ymin=max_xy[1], xmin=min_xy[0], lx=trench_dx, ly=trench_width,
layer=trench_layer, dose=trench_dose),
Polygon.rect(ymax=min_xy[1], xmin=min_xy[0], lx=trench_dx, ly=trench_width,
layer=trench_layer, dose=trench_dose),
]
# Ports are at outer extents of the device (with y=0)
extent = lattice_constant * xy_size[0]
ports = {
'input': Port((-extent, 0), rotation=0, ptype='pcwg'),
'output': Port((extent, 0), rotation=pi, ptype='pcwg'),
}
return Device(pat, ports)
def waveguide(
lattice_constant: float,
hole: Pattern,
length: int,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a photonic crystal line-defect waveguide.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
length: Distance (number of mirror periods) between the input and output ports.
Ports are placed at lattice sites.
mirror_periods: Number of hole rows on each side of the line defect
Returns:
`Device` object representing the waveguide.
"""
# Generate hole locations
xy = pcgen.waveguide(length=length, num_mirror=mirror_periods)
# Build the pattern
pat = Pattern(f'_wg-a{lattice_constant:g}l{length}')
pat.subpatterns += [SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
# Ports are at outer edges, with y=0
extent = lattice_constant * length / 2
ports = {
'left': Port((-extent, 0), rotation=0, ptype='pcwg'),
'right': Port((extent, 0), rotation=pi, ptype='pcwg'),
}
return Device(pat, ports)
def bend(
lattice_constant: float,
hole: Pattern,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a 60-degree counterclockwise bend in a photonic crystal
line-defect waveguide.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
mirror_periods: Minimum number of mirror periods on each side of the line defect.
Returns:
`Device` object representing the waveguide bend.
Ports are named 'left' (input) and 'right' (output).
"""
# Generate hole locations
xy = pcgen.wgbend(num_mirror=mirror_periods)
# Build the pattern
pat= Pattern(f'_wgbend-a{lattice_constant:g}l{mirror_periods}')
pat.subpatterns += [
SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
# Figure out port locations.
extent = lattice_constant * mirror_periods
ports = {
'left': Port((-extent, 0), rotation=0, ptype='pcwg'),
'right': Port((extent / 2,
extent * numpy.sqrt(3) / 2),
rotation=pi * 4 / 3, ptype='pcwg'),
}
return Device(pat, ports)
def y_splitter(
lattice_constant: float,
hole: Pattern,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a photonic crystal line-defect waveguide y-splitter.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
mirror_periods: Minimum number of mirror periods on each side of the line defect.
Returns:
`Device` object representing the y-splitter.
Ports are named 'in', 'top', and 'bottom'.
"""
# Generate hole locations
xy = pcgen.y_splitter(num_mirror=mirror_periods)
# Build pattern
pat = Pattern(f'_wgsplit_half-a{lattice_constant:g}l{mirror_periods}')
pat.subpatterns += [
SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
# Determine port locations
extent = lattice_constant * mirror_periods
ports = {
'in': Port((-extent, 0), rotation=0, ptype='pcwg'),
'top': Port((extent / 2, extent * numpy.sqrt(3) / 2), rotation=pi * 4 / 3, ptype='pcwg'),
'bot': Port((extent / 2, -extent * numpy.sqrt(3) / 2), rotation=pi * 2 / 3, ptype='pcwg'),
}
return Device(pat, ports)
def dev2pat(device: Device, layer: layer_t = (3, 0)) -> Pattern:
"""
Place a text label at each port location, specifying the port data.
This can be used to debug port locations or to automatically generate ports
when reading in a GDS file.
NOTE that `device` is modified by this function, and `device.pattern` is returned.
Args:
device: The device which is to have its ports labeled. MODIFIED in-place.
layer: The layer on which the labels will be placed.
Returns:
`device.pattern`
"""
for name, port in device.ports.items():
if port.rotation is None:
angle_deg = numpy.inf
else:
angle_deg = numpy.rad2deg(port.rotation)
device.pattern.labels += [
Label(string=f'{name}:{port.ptype} {angle_deg:g}', layer=layer, offset=port.offset)
]
return device.pattern
def pat2dev(
pattern: Pattern,
layers: Sequence[layer_t] = ((3, 0),),
max_depth: int = 999_999,
skip_subcells: bool = True,
) -> Device:
ports = {} # Note: could do a list here, if they're not unique
annotated_cells = set()
def find_ports_each(pat, hierarchy, transform, memo) -> Pattern:
if len(hierarchy) > max_depth - 1:
return pat
if skip_subcells and any(parent in annotated_cells for parent in hierarchy):
return pat
labels = [ll for ll in pat.labels if ll.layer in layers]
if len(labels) == 0:
return pat
if skip_subcells:
annotated_cells.add(pat)
mirr_factor = numpy.array((1, -1)) ** transform[3]
rot_matrix = rotation_matrix_2d(transform[2])
for label in labels:
name, property_string = label.string.split(':')
properties = property_string.split(' ')
ptype = properties[0]
angle_deg = float(properties[1]) if len(ptype) else 0
xy_global = transform[:2] + rot_matrix @ (label.offset * mirr_factor)
angle = numpy.deg2rad(angle_deg) * mirr_factor[0] * mirr_factor[1] + transform[2]
if name in ports:
raise Exception('Duplicate port name in pattern!')
ports[name] = Port(offset=xy_global, rotation=angle, ptype=ptype)
return pat
pattern.dfs(visit_before=find_ports_each, transform=True)
return Device(pattern, ports)
def main(interactive: bool = True):
# Generate some basic hole patterns
smile = basic_shapes.smile(RADIUS)
hole = basic_shapes.hole(RADIUS)
# Build some devices
a = LATTICE_CONSTANT
wg10 = waveguide(lattice_constant=a, hole=hole, length=10, mirror_periods=5).rename('wg10')
wg05 = waveguide(lattice_constant=a, hole=hole, length=5, mirror_periods=5).rename('wg05')
wg28 = waveguide(lattice_constant=a, hole=hole, length=28, mirror_periods=5).rename('wg28')
bend0 = bend(lattice_constant=a, hole=hole, mirror_periods=5).rename('bend0')
ysplit = y_splitter(lattice_constant=a, hole=hole, mirror_periods=5).rename('ysplit')
l3cav = perturbed_l3(lattice_constant=a, hole=smile, xy_size=(4, 10)).rename('l3cav') # uses smile :)
# Autogenerate port labels so that GDS will also contain port data
for device in [wg10, wg05, wg28, l3cav, ysplit, bend0]:
dev2pat(device)
#
# Build a circuit
#
circ = Device(name='my_circuit', ports={})
# Start by placing a waveguide. Call its ports "in" and "signal".
circ.place(wg10, offset=(0, 0), port_map={'left': 'in', 'right': 'signal'})
# Extend the signal path by attaching the "left" port of a waveguide.
# Since there is only one other port ("right") on the waveguide we
# are attaching (wg10), it automatically inherits the name "signal".
circ.plug(wg10, {'signal': 'left'})
# Attach a y-splitter to the signal path.
# Since the y-splitter has 3 ports total, we can't auto-inherit the
# port name, so we have to specify what we want to name the unattached
# ports. We can call them "signal1" and "signal2".
circ.plug(ysplit, {'signal': 'in'}, {'top': 'signal1', 'bot': 'signal2'})
# Add a waveguide to both signal ports, inheriting their names.
circ.plug(wg05, {'signal1': 'left'})
circ.plug(wg05, {'signal2': 'left'})
# Add a bend to both ports.
# Our bend's ports "left" and "right" refer to the original counterclockwise
# orientation. We want the bends to turn in opposite directions, so we attach
# the "right" port to "signal1" to bend clockwise, and the "left" port
# to "signal2" to bend counterclockwise.
# We could also use `mirrored=(True, False)` to mirror one of the devices
# and then use same device port on both paths.
circ.plug(bend0, {'signal1': 'right'})
circ.plug(bend0, {'signal2': 'left'})
# We add some waveguides and a cavity to "signal1".
circ.plug(wg10, {'signal1': 'left'})
circ.plug(l3cav, {'signal1': 'input'})
circ.plug(wg10, {'signal1': 'left'})
# "signal2" just gets a single of equivalent length
circ.plug(wg28, {'signal2': 'left'})
# Now we bend both waveguides back towards each other
circ.plug(bend0, {'signal1': 'right'})
circ.plug(bend0, {'signal2': 'left'})
circ.plug(wg05, {'signal1': 'left'})
circ.plug(wg05, {'signal2': 'left'})
# To join the waveguides, we attach a second y-junction.
# We plug "signal1" into the "bot" port, and "signal2" into the "top" port.
# The remaining port gets named "signal_out".
# This operation would raise an exception if the ports did not line up
# correctly (i.e. they required different rotations or translations of the
# y-junction device).
circ.plug(ysplit, {'signal1': 'bot', 'signal2': 'top'}, {'in': 'signal_out'})
# Finally, add some more waveguide to "signal_out".
circ.plug(wg10, {'signal_out': 'left'})
# We can visualize the design. Usually it's easier to just view the GDS.
if interactive:
print('Visualizing... this step may be slow')
circ.pattern.visualize()
# We can also add text labels for our circuit's ports.
# They will appear at the uppermost hierarchy level, while the individual
# device ports will appear further down, in their respective cells.
dev2pat(circ)
# Write out to GDS
writefile(circ.pattern, 'circuit.gds', **GDS_OPTS)
if __name__ == '__main__':
main()

136
examples/tutorial/library.py Normal file
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@ -0,0 +1,136 @@
from typing import Tuple, Sequence, Callable
from pprint import pformat
import numpy
from numpy import pi
from masque.builder import Device
from masque.library import Library, LibDeviceLibrary
from masque.file.gdsii import writefile, load_libraryfile
import pcgen
import basic_shapes
import devices
from basic_shapes import GDS_OPTS
def main() -> None:
# Define a `Library`-backed `DeviceLibrary`, which provides lazy evaluation
# for device generation code and lazy-loading of GDS contents.
device_lib = LibDeviceLibrary()
#
# Load some devices from a GDS file
#
# Scan circuit.gds and prepare to lazy-load its contents
pattern_lib, _properties = load_libraryfile('circuit.gds', tag='mycirc01')
# Add it into the device library by providing a way to read port info
# This maintains the lazy evaluation from above, so no patterns
# are actually read yet.
device_lib.add_library(pattern_lib, pat2dev=devices.pat2dev)
print('Devices loaded from GDS into library:\n' + pformat(list(device_lib.keys())))
#
# Add some new devices to the library, this time from python code rather than GDS
#
a = devices.LATTICE_CONSTANT
tri = basic_shapes.triangle(devices.RADIUS)
# Convenience function for adding devices
# This is roughly equivalent to
# `device_lib[name] = lambda: devices.dev2pat(fn())`
# but it also guarantees that the resulting pattern is named `name`.
def add(name: str, fn: Callable[[], Device]) -> None:
device_lib.add_device(name=name, fn=fn, dev2pat=devices.dev2pat)
# Triangle-based variants. These are defined here, but they won't run until they're
# retrieved from the library.
add('tri_wg10', lambda: devices.waveguide(lattice_constant=a, hole=tri, length=10, mirror_periods=5))
add('tri_wg05', lambda: devices.waveguide(lattice_constant=a, hole=tri, length=5, mirror_periods=5))
add('tri_wg28', lambda: devices.waveguide(lattice_constant=a, hole=tri, length=28, mirror_periods=5))
add('tri_bend0', lambda: devices.bend(lattice_constant=a, hole=tri, mirror_periods=5))
add('tri_ysplit', lambda: devices.y_splitter(lattice_constant=a, hole=tri, mirror_periods=5))
add('tri_l3cav', lambda: devices.perturbed_l3(lattice_constant=a, hole=tri, xy_size=(4, 10)))
#
# Build a mixed waveguide with an L3 cavity in the middle
#
# Immediately start building from an instance of the L3 cavity
circ2 = device_lib['tri_l3cav'].build('mixed_wg_cav')
print(device_lib['wg10'].ports)
circ2.plug(device_lib['wg10'], {'input': 'right'})
circ2.plug(device_lib['wg10'], {'output': 'left'})
circ2.plug(device_lib['tri_wg10'], {'input': 'right'})
circ2.plug(device_lib['tri_wg10'], {'output': 'left'})
# Add the circuit to the device library.
# It has already been generated, so we can use `set_const` as a shorthand for
# `device_lib['mixed_wg_cav'] = lambda: circ2`
device_lib.set_const(circ2)
#
# Build a device that could plug into our mixed_wg_cav and joins the two ports
#
# We'll be designing against an existing device's interface...
circ3 = circ2.as_interface('loop_segment')
# ... that lets us continue from where we left off.
circ3.plug(device_lib['tri_bend0'], {'input': 'right'})
circ3.plug(device_lib['tri_bend0'], {'input': 'left'}, mirrored=(True, False)) # mirror since no tri y-symmetry
circ3.plug(device_lib['tri_bend0'], {'input': 'right'})
circ3.plug(device_lib['bend0'], {'output': 'left'})
circ3.plug(device_lib['bend0'], {'output': 'left'})
circ3.plug(device_lib['bend0'], {'output': 'left'})
circ3.plug(device_lib['tri_wg10'], {'input': 'right'})
circ3.plug(device_lib['tri_wg28'], {'input': 'right'})
circ3.plug(device_lib['tri_wg10'], {'input': 'right', 'output': 'left'})
device_lib.set_const(circ3)
#
# Write all devices into a GDS file
#
# This line could be slow, since it generates or loads many of the devices
# since they were not all accessed above.
all_device_pats = [dev.pattern for dev in device_lib.values()]
writefile(all_device_pats, 'library.gds', **GDS_OPTS)
if __name__ == '__main__':
main()
#
#class prout:
# def place(
# self,
# other: Device,
# label_layer: layer_t = 'WATLAYER',
# *,
# port_map: Optional[Dict[str, Optional[str]]] = None,
# **kwargs,
# ) -> 'prout':
#
# Device.place(self, other, port_map=port_map, **kwargs)
# name: Optional[str]
# for name in other.ports:
# if port_map:
# assert(name is not None)
# name = port_map.get(name, name)
# if name is None:
# continue
# self.pattern.labels += [
# Label(string=name, offset=self.ports[name].offset, layer=layer)]
# return self
#

251
examples/tutorial/phc.py
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@ -1,251 +0,0 @@
from typing import Tuple, Sequence
import numpy
from numpy import pi
from masque import layer_t, Pattern, SubPattern, Label
from masque.shapes import Polygon, Circle
from masque.builder import Device, Port
from masque.library import Library, DeviceLibrary
from masque.file.gdsii import writefile
import pcgen
import basic
def perturbed_l3(
lattice_constant: float,
hole: Pattern,
trench_dose: float = 1.0,
trench_layer: layer_t = (1, 0),
shifts_a: Sequence[float] = (0.15, 0, 0.075),
shifts_r: Sequence[float] = (1.0, 1.0, 1.0),
xy_size: Tuple[int, int] = (10, 10),
perturbed_radius: float = 1.1,
trench_width: float = 1200,
) -> Device:
"""
Generate a `Device` representing a perturbed L3 cavity.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
trench_dose: Dose for the trenches. Default 1.0. (Hole dose is 1.0.)
trench_layer: Layer for the trenches, default `(1, 0)`.
shifts_a: passed to `pcgen.l3_shift`; specifies lattice constant
(1 - multiplicative factor) for shifting holes adjacent to
the defect (same row). Default `(0.15, 0, 0.075)` for first,
second, third holes.
shifts_r: passed to `pcgen.l3_shift`; specifies radius for perturbing
holes adjacent to the defect (same row). Default 1.0 for all holes.
Provided sequence should have same length as `shifts_a`.
xy_size: `(x, y)` number of mirror periods in each direction; total size is
`2 * n + 1` holes in each direction. Default (10, 10).
perturbed_radius: radius of holes perturbed to form an upwards-driected beam
(multiplicative factor). Default 1.1.
trench width: Width of the undercut trenches. Default 1200.
Returns:
`Device` object representing the L3 design.
"""
xyr = pcgen.l3_shift_perturbed_defect(mirror_dims=xy_size,
perturbed_radius=perturbed_radius,
shifts_a=shifts_a,
shifts_r=shifts_r)
pat = Pattern(f'L3p-a{lattice_constant:g}rp{perturbed_radius:g}')
pat.subpatterns += [SubPattern(hole,
offset=(lattice_constant * x,
lattice_constant * y),
scale=r)
for x, y, r in xyr]
bounds = pat.get_bounds()
assert(bounds is not None)
min_xy, max_xy = bounds
trench_dx = max_xy[0] - min_xy[0]
pat.shapes += [
Polygon.rect(ymin=max_xy[1], xmin=min_xy[0], lx=trench_dx, ly=trench_width,
layer=trench_layer, dose=trench_dose),
Polygon.rect(ymax=min_xy[1], xmin=min_xy[0], lx=trench_dx, ly=trench_width,
layer=trench_layer, dose=trench_dose),
]
extent = lattice_constant * xy_size[0]
ports = {
'input': Port((-extent, 0), rotation=0, ptype='pcwg'),
'output': Port((extent, 0), rotation=pi, ptype='pcwg'),
}
return Device(pat, ports)
def waveguide(
lattice_constant: float,
hole: Pattern,
length: int,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a photonic crystal line-defect waveguide.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
length: Distance (number of mirror periods) between the input and output ports.
Ports are placed at lattice sites.
mirror_periods: Number of hole rows on each side of the line defect
Returns:
`Device` object representing the waveguide.
"""
xy = pcgen.waveguide(length=length, num_mirror=mirror_periods)
pat = Pattern(f'_wg-a{lattice_constant:g}l{length}')
pat.subpatterns += [SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
extent = lattice_constant * length / 2
ports = {
'left': Port((-extent, 0), rotation=0, ptype='pcwg'),
'right': Port((extent, 0), rotation=pi, ptype='pcwg'),
}
return Device(pat, ports)
def bend(
lattice_constant: float,
hole: Pattern,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a 60-degree counterclockwise bend in a photonic crystal
line-defect waveguide.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
mirror_periods: Minimum number of mirror periods on each side of the line defect.
Returns:
`Device` object representing the waveguide bend.
Ports are named 'left' (input) and 'right' (output).
"""
xy = pcgen.wgbend(num_mirror=mirror_periods)
pat= Pattern(f'_wgbend-a{lattice_constant:g}l{mirror_periods}')
pat.subpatterns += [SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
extent = lattice_constant * mirror_periods
ports = {
'left': Port((-extent, 0), rotation=0, ptype='pcwg'),
'right': Port((extent / 2,
extent * numpy.sqrt(3) / 2), rotation=pi * 4 / 3, ptype='pcwg'),
}
return Device(pat, ports)
def y_splitter(
lattice_constant: float,
hole: Pattern,
mirror_periods: int,
) -> Device:
"""
Generate a `Device` representing a photonic crystal line-defect waveguide y-splitter.
Args:
lattice_constant: Distance between nearest neighbor holes
hole: `Pattern` object containing a single hole
mirror_periods: Minimum number of mirror periods on each side of the line defect.
Returns:
`Device` object representing the y-splitter.
Ports are named 'in', 'top', and 'bottom'.
"""
xy = pcgen.y_splitter(num_mirror=mirror_periods)
pat = Pattern(f'_wgsplit_half-a{lattice_constant:g}l{mirror_periods}')
pat.subpatterns += [SubPattern(hole, offset=(lattice_constant * x,
lattice_constant * y))
for x, y in xy]
extent = lattice_constant * mirror_periods
ports = {
'in': Port((-extent, 0), rotation=0, ptype='pcwg'),
'top': Port((extent / 2,
extent * numpy.sqrt(3) / 2), rotation=pi * 4 / 3, ptype='pcwg'),
'bot': Port((extent / 2,
-extent * numpy.sqrt(3) / 2), rotation=pi * 2 / 3, ptype='pcwg'),
}
return Device(pat, ports)
def label_ports(device: Device, layer: layer_t = (3, 0)) -> Device:
"""
Place a text label at each port location, specifying the port data.
This can be used to debug port locations or to automatically generate ports
when reading in a GDS file.
Args:
device: The device which is to have its ports labeled.
layer: The layer on which the labels will be placed.
Returns:
`device` is returned (and altered in-place)
"""
for name, port in device.ports.items():
angle_deg = numpy.rad2deg(port.rotation) if port.rotation is not None else numpy.inf
device.pattern.labels += [
Label(string=f'{name} (angle {angle_deg:g})', layer=layer, offset=port.offset)
]
return device
def main():
a = 512
radius = a / 2 * 0.75
smile = basic.smile(radius)
hole = basic.hole(radius)
wg10 = label_ports(waveguide(lattice_constant=a, hole=hole, length=10, mirror_periods=5))
wg05 = label_ports(waveguide(lattice_constant=a, hole=hole, length=5, mirror_periods=5))
wg28 = label_ports(waveguide(lattice_constant=a, hole=hole, length=28, mirror_periods=5))
bend0 = label_ports(bend(lattice_constant=a, hole=hole, mirror_periods=5))
l3cav = label_ports(perturbed_l3(lattice_constant=a, hole=smile, xy_size=(4, 10)))
ysplit = label_ports(y_splitter(lattice_constant=a, hole=hole, mirror_periods=5))
dev = Device(name='my_bend', ports={})
dev.place(wg10, offset=(0, 0), port_map={'left': 'in', 'right': 'signal'})
dev.plug(wg10, {'signal': 'left'})
dev.plug(ysplit, {'signal': 'in'}, {'top': 'signal1', 'bot': 'signal2'})
dev.plug(wg05, {'signal1': 'left'})
dev.plug(wg05, {'signal2': 'left'})
dev.plug(bend0, {'signal1': 'right'})
dev.plug(bend0, {'signal2': 'left'})
dev.plug(wg10, {'signal1': 'left'})
dev.plug(l3cav, {'signal1': 'input'})
dev.plug(wg10, {'signal1': 'left'})
dev.plug(wg28, {'signal2': 'left'})
dev.plug(bend0, {'signal1': 'right'})
dev.plug(bend0, {'signal2': 'left'})
dev.plug(wg05, {'signal1': 'left'})
dev.plug(wg05, {'signal2': 'left'})
dev.plug(ysplit, {'signal1': 'bot', 'signal2': 'top'}, {'in': 'signal_out'})
dev.plug(wg10, {'signal_out': 'left'})
writefile(dev.pattern, 'phc.gds', 1e-9, 1e-3)
dev.pattern.visualize()
if __name__ == '__main__':
main()