# -*- 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.
import numpy as np
from qiskit_metal import draw, Dict
from qiskit_metal.qlibrary.core import BaseQubit
[docs]
class TransmonCross(BaseQubit): # pylint: disable=invalid-name
"""The base `TransmonCross` class.
Inherits `BaseQubit` class.
Simple Metal Transmon Cross object. Creates the X cross-shaped island,
the "junction" on the south end, and up to 3 connectors on the remaining arms
(claw or gap).
'claw_width' and 'claw_gap' define the width/gap of the CPW line that
makes up the connector. Note, DC SQUID currently represented by single
inductance sheet
Add connectors to it using the `connection_pads` dictionary. See BaseQubit for more
information.
Sketch:
Below is a sketch of the qubit
::
claw_length
Claw: _________ Gap:
| ________________ _________ ____________
______| | _________| |____________
| |________________
|_________
.. image::
transmon_cross.png
.. meta::
Transmon Cross
BaseQubit Default Options:
* connection_pads: Empty Dict -- The dictionary which contains all active connection lines for the qubit.
* _default_connection_pads: empty Dict -- The default values for the (if any) connection lines of the qubit.
Default Options:
* cross_width: '20um' -- Width of the CPW center trace making up the Crossmon
* cross_length: '200um' -- Length of one Crossmon arm (from center)
* cross_gap: '20um' -- Width of the CPW gap making up the Crossmon
* _default_connection_pads: Dict
* connector_type: '0' -- 0 = Claw type, 1 = gap type
* claw_length: '30um' -- Length of the claw 'arms', measured from the connector center trace
* ground_spacing: '5um' -- Amount of ground plane between the connector and Crossmon arm (minimum should be based on fabrication capabilities)
* claw_width: '10um' -- The width of the CPW center trace making up the claw/gap connector
* claw_gap: '6um' -- The gap of the CPW center trace making up the claw/gap connector
* connector_location: '0' -- 0 => 'west' arm, 90 => 'north' arm, 180 => 'east' arm
"""
default_options = Dict(
cross_width='20um',
cross_length='200um',
cross_gap='20um',
chip='main',
_default_connection_pads=Dict(
connector_type='0', # 0 = Claw type, 1 = gap type
claw_length='30um',
ground_spacing='5um',
claw_width='10um',
claw_gap='6um',
claw_cpw_length='40um',
claw_cpw_width='10um',
connector_location=
'0' # 0 => 'west' arm, 90 => 'north' arm, 180 => 'east' arm
))
"""Default options."""
component_metadata = Dict(short_name='Cross',
_qgeometry_table_poly='True',
_qgeometry_table_junction='True')
"""Component metadata"""
TOOLTIP = """Simple Metal Transmon Cross."""
##############################################MAKE######################################################
[docs]
def make(self):
"""This is executed by the GUI/user to generate the qgeometry for the
component."""
self.make_pocket()
self.make_connection_pads()
###################################TRANSMON#############################################################
[docs]
def make_pocket(self):
"""Makes a basic Crossmon, 4 arm cross."""
# self.p allows us to directly access parsed values (string -> numbers) form the user option
p = self.p
cross_width = p.cross_width
cross_length = p.cross_length
cross_gap = p.cross_gap
# access to chip name
chip = p.chip
# Creates the cross and the etch equivalent.
cross_line = draw.shapely.ops.unary_union([
draw.LineString([(0, cross_length), (0, -cross_length)]),
draw.LineString([(cross_length, 0), (-cross_length, 0)])
])
cross = cross_line.buffer(cross_width / 2, cap_style=2)
cross_etch = cross.buffer(cross_gap, cap_style=3, join_style=2)
# The junction/SQUID
#rect_jj = draw.rectangle(cross_width, cross_gap)
#rect_jj = draw.translate(rect_jj, 0, -cross_length-cross_gap/2)
rect_jj = draw.LineString([(0, -cross_length),
(0, -cross_length - cross_gap)])
#rotate and translate
polys = [cross, cross_etch, rect_jj]
polys = draw.rotate(polys, p.orientation, origin=(0, 0))
polys = draw.translate(polys, p.pos_x, p.pos_y)
[cross, cross_etch, rect_jj] = polys
# generate qgeometry
self.add_qgeometry('poly', dict(cross=cross), chip=chip)
self.add_qgeometry('poly',
dict(cross_etch=cross_etch),
subtract=True,
chip=chip)
self.add_qgeometry('junction',
dict(rect_jj=rect_jj),
width=cross_width,
chip=chip)
############################CONNECTORS##################################################################################################
[docs]
def make_connection_pads(self):
"""Goes through connector pads and makes each one."""
for name in self.options.connection_pads:
self.make_connection_pad(name)
[docs]
def make_connection_pad(self, name: str):
"""Makes individual connector pad.
Args:
name (str) : Name of the connector pad
"""
# self.p allows us to directly access parsed values (string -> numbers) form the user option
p = self.p
cross_width = p.cross_width
cross_length = p.cross_length
cross_gap = p.cross_gap
# access to chip name
chip = p.chip
pc = self.p.connection_pads[name] # parser on connector options
c_g = pc.claw_gap
c_l = pc.claw_length
c_w = pc.claw_width
c_c_w = pc.claw_cpw_width
c_c_l = pc.claw_cpw_length
g_s = pc.ground_spacing
con_loc = pc.connector_location
claw_cpw = draw.box(-c_w, -c_c_w / 2, -c_c_l - c_w, c_c_w / 2)
if pc.connector_type == 0: # Claw connector
t_claw_height = 2*c_g + 2 * c_w + 2*g_s + \
2*cross_gap + cross_width # temp value
claw_base = draw.box(-c_w, -(t_claw_height) / 2, c_l,
t_claw_height / 2)
claw_subtract = draw.box(0, -t_claw_height / 2 + c_w, c_l,
t_claw_height / 2 - c_w)
claw_base = claw_base.difference(claw_subtract)
connector_arm = draw.shapely.ops.unary_union([claw_base, claw_cpw])
connector_etcher = draw.buffer(connector_arm, c_g)
else:
connector_arm = draw.box(0, -c_w / 2, -4 * c_w, c_w / 2)
connector_etcher = draw.buffer(connector_arm, c_g)
# Making the pin for tracking (for easy connect functions).
# Done here so as to have the same translations and rotations as the connector. Could
# extract from the connector later, but since allowing different connector types,
# this seems more straightforward.
port_line = draw.LineString([(-c_c_l - c_w, -c_c_w / 2),
(-c_c_l - c_w, c_w / 2)])
claw_rotate = 0
if con_loc > 135:
claw_rotate = 180
elif con_loc > 45:
claw_rotate = -90
# Rotates and translates the connector polygons (and temporary port_line)
polys = [connector_arm, connector_etcher, port_line]
polys = draw.translate(polys, -(cross_length + cross_gap + g_s + c_g),
0)
polys = draw.rotate(polys, claw_rotate, origin=(0, 0))
polys = draw.rotate(polys, p.orientation, origin=(0, 0))
polys = draw.translate(polys, p.pos_x, p.pos_y)
[connector_arm, connector_etcher, port_line] = polys
# Generates qgeometry for the connector pads
self.add_qgeometry('poly', {f'{name}_connector_arm': connector_arm},
chip=chip)
self.add_qgeometry('poly',
{f'{name}_connector_etcher': connector_etcher},
subtract=True,
chip=chip)
self.add_pin(name, port_line.coords, c_c_w)