# -*- coding: utf-8 -*-
# This code is part of Qiskit.
#
# (C) Copyright IBM 2017, 2021.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
from qiskit_metal import draw, Dict
from qiskit_metal.qlibrary.core import QComponent
import numpy as np
[docs]
class CapNInterdigitalTee(QComponent):
"""Generates a three pin (+) structure comprised of a primary two pin CPW
transmission line, and a secondary one pin neighboring CPW transmission
line that is capacitively coupled to the primary. Such a structure can be
used, as an example, for generating CPW resonator hangars off of a
transmission line. (0,0) represents the center position of the component.
Setting finger length to 0 gives a simple gap capacitor.
Inherits QComponent class.
::
(0,0)
+--------------------------+
|
--|-----|--
| | | | |
|-----|-----|
|
|
|
|
+
.. image::
CapNInterdigitalTee.png
.. meta::
:description: Cap N Interdigital Tee
Options:
* prime_width: '10um' -- The width of the trace of the two pin CPW transmission line
* prime_gap: '6um' -- The dielectric gap of the two pin CPW transmission line
* second_width: '10um' -- The width of the trace of the one pin CPW transmission line
* second_gap: '6um' -- The dielectric gap of the one pin CPW transmission line (also for the capacitor)
* cap_gap: '6um' -- The width of dielectric for the capacitive coupling (default same as second_gap)
* cap_width: '10um' -- The width of the finger capacitor (default same as second)
* finger_length: '20um' -- The depth of the charge islands of the capacitor
* finger_count: '5' -- Number of fingers in the capacitor
* cap_distance: '50um' -- Distance of capacitor from center transmission line
"""
component_metadata = Dict(
short_name="cpw", _qgeometry_table_poly="True", _qgeometry_table_path="True"
)
"""Component metadata"""
# Currently setting the primary CPW length based on the coupling_length
# May want it to be it's own value that the user can control?
default_options = Dict(
prime_width="10um",
prime_gap="6um",
second_width="10um",
second_gap="6um",
cap_gap="6um",
cap_width="10um",
finger_length="20um",
finger_count="5",
cap_distance="50um",
)
"""Default connector options"""
TOOLTIP = """Generates a three pin (+) structure comprised of a primary two pin CPW
transmission line, and a secondary one pin neighboring CPW transmission
line that is capacitively coupled to the primary."""
[docs]
def make(self):
"""Build the component."""
p = self.p
N = int(p.finger_count)
prime_cpw_length = p.cap_width * 2 * N
# Primary CPW
prime_cpw = draw.LineString(
[[-prime_cpw_length / 2, 0], [prime_cpw_length / 2, 0]]
)
# Finger Capacitor
cap_box = draw.rectangle(
N * p.cap_width + (N - 1) * p.cap_gap,
p.cap_gap + 2 * p.cap_width + p.finger_length,
0,
0,
)
make_cut_list = []
make_cut_list.append([0, (p.finger_length) / 2])
make_cut_list.append([(p.cap_width) + (p.cap_gap / 2), (p.finger_length) / 2])
flip = -1
for i in range(1, N):
make_cut_list.append(
[
i * (p.cap_width) + (2 * i - 1) * (p.cap_gap / 2),
flip * (p.finger_length) / 2,
]
)
make_cut_list.append(
[
(i + 1) * (p.cap_width) + (2 * i + 1) * (p.cap_gap / 2),
flip * (p.finger_length) / 2,
]
)
flip = flip * -1
cap_cut = draw.LineString(make_cut_list).buffer(
p.cap_gap / 2, cap_style=2, join_style=2
)
cap_cut = draw.translate(
cap_cut, -(N * p.cap_width + (N - 1) * p.cap_gap) / 2, 0
)
cap_body = draw.subtract(cap_box, cap_cut)
cap_body = draw.translate(
cap_body,
0,
-p.cap_distance - (p.cap_gap + 2 * p.cap_width + p.finger_length) / 2,
)
cap_etch = draw.rectangle(
N * p.cap_width + (N - 1) * p.cap_gap + 2 * p.second_gap,
p.cap_gap + 2 * p.cap_width + p.finger_length + 2 * p.second_gap,
0,
-p.cap_distance - (p.cap_gap + 2 * p.cap_width + p.finger_length) / 2,
)
# Secondary CPW
second_cpw_top = draw.LineString(
[[0, -p.prime_width / 2], [0, -p.cap_distance]]
)
second_cpw_bottom = draw.LineString(
[
[0, -p.cap_distance - (p.cap_gap + 2 * p.cap_width + p.finger_length)],
[
0,
-2 * p.cap_distance
- (p.cap_gap + 2 * p.cap_width + p.finger_length),
],
]
)
# Rotate and Translate
c_items = [prime_cpw, second_cpw_top, second_cpw_bottom, cap_body, cap_etch]
c_items = draw.rotate(c_items, p.orientation, origin=(0, 0))
c_items = draw.translate(c_items, p.pos_x, p.pos_y)
[prime_cpw, second_cpw_top, second_cpw_bottom, cap_body, cap_etch] = c_items
# Add to qgeometry tables
self.add_qgeometry(
"path", {"prime_cpw": prime_cpw}, width=p.prime_width, layer=p.layer
)
self.add_qgeometry(
"path",
{"prime_cpw_sub": prime_cpw},
width=p.prime_width + 2 * p.prime_gap,
subtract=True,
layer=p.layer,
)
self.add_qgeometry(
"path",
{"second_cpw_top": second_cpw_top, "second_cpw_bottom": second_cpw_bottom},
width=p.second_width,
layer=p.layer,
)
self.add_qgeometry(
"path",
{
"second_cpw_top_sub": second_cpw_top,
"second_cpw_bottom_sub": second_cpw_bottom,
},
width=p.second_width + 2 * p.second_gap,
subtract=True,
layer=p.layer,
)
self.add_qgeometry("poly", {"cap_body": cap_body}, layer=p.layer)
self.add_qgeometry("poly", {"cap_etch": cap_etch}, layer=p.layer, subtract=True)
# Add pins
prime_pin_list = prime_cpw.coords
second_pin_list = second_cpw_bottom.coords
self.add_pin(
"prime_start",
points=np.array(prime_pin_list[::-1]),
width=p.prime_width,
input_as_norm=True,
)
self.add_pin(
"prime_end",
points=np.array(prime_pin_list),
width=p.prime_width,
input_as_norm=True,
)
self.add_pin(
"second_end",
points=np.array(second_pin_list),
width=p.second_width,
input_as_norm=True,
)