# This code is part of KQCircuits
# Copyright (C) 2025 IQM Finland Oy
#
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import math
from kqcircuits.pya_resolver import pya
from kqcircuits.simulations.epr.util import create_bulk_and_mer_partition_regions
[docs]
def partition_regions(simulation):
"""Returns list of PartitionRegion objects for Circular Transmon Single Island EPR simulation."""
regions = []
# Coupler partition regions - one for each coupler
for i, (c_angle, c_arc_ampl) in enumerate(zip(simulation.couplers_angle, simulation.couplers_arc_amplitude)):
# Create pizza slice shape for each coupler
c_angle_rad = math.radians(float(c_angle))
c_arc_ampl_rad = math.radians(float(c_arc_ampl))
# Inner radius (closer to qubit center, with some margin)
inner_radius = simulation.r_island - 10
# Outer radius (extends beyond coupler, with extra space)
outer_radius = simulation.r_island + simulation.ground_gap + 20
# Angular extent with extra margin
half_angle = c_arc_ampl_rad / 2 + math.radians(10) # Extra 10 degrees on each side
# Create pizza slice polygon without center point to avoid zero width lines
points = []
# Add arc points for outer edge
n_points = 32
for j in range(n_points + 1):
angle = c_angle_rad - half_angle + (2 * half_angle * j) / n_points
x = outer_radius * math.cos(angle)
y = outer_radius * math.sin(angle)
points.append(pya.DPoint(x, y) + simulation.refpoints["base"])
# Add arc points for inner edge (reverse direction)
for j in range(n_points, -1, -1):
angle = c_angle_rad - half_angle + (2 * half_angle * j) / n_points
x = inner_radius * math.cos(angle)
y = inner_radius * math.sin(angle)
points.append(pya.DPoint(x, y) + simulation.refpoints["base"])
coupler_region = pya.DPolygon(points)
regions += create_bulk_and_mer_partition_regions(
name=f"{i}cplr",
face=simulation.face_ids[0],
metal_edge_dimensions=2.0,
region=coupler_region,
vertical_dimensions=3.0,
bulk=False,
visualise=True,
)
# Junction hall partition region
squid_angle_rad = math.radians(simulation.squid_angle)
hall_length = simulation.ground_gap + 10 # Extra space
hall_width = 8 + 4 # Junction hall width + extra space
# Create rotated rectangle for junction hall
hall_rect = pya.DPolygon(
[
pya.DPoint(-hall_width / 2, 0),
pya.DPoint(hall_width / 2, 0),
pya.DPoint(hall_width / 2, hall_length),
pya.DPoint(-hall_width / 2, hall_length),
]
)
# Position at island edge and rotate
junction_pos = pya.DPoint(
simulation.r_island * math.cos(squid_angle_rad), simulation.r_island * math.sin(squid_angle_rad)
)
hall_transform = pya.DCplxTrans(1, simulation.squid_angle - 90, False, junction_pos + simulation.refpoints["base"])
hall_region = hall_transform * hall_rect
regions += create_bulk_and_mer_partition_regions(
name="leads",
face=simulation.face_ids[0],
metal_edge_dimensions=2.0,
region=hall_region,
vertical_dimensions=3.0,
bulk=False,
visualise=True,
)
# Main island complement region
regions += create_bulk_and_mer_partition_regions(
name=f"{simulation.face_ids[0]}complement",
face=simulation.face_ids[0],
metal_edge_dimensions=2.0,
region=None,
vertical_dimensions=3.0,
bulk=False,
visualise=True,
)
return regions
[docs]
def correction_cuts(simulation):
"""Returns dictionary of correction cuts for Circular Transmon Single Island EPR simulation."""
cuts = {}
# Coupler correction cuts
for i, (c_angle, c_arc_ampl) in enumerate(zip(simulation.couplers_angle, simulation.couplers_arc_amplitude)):
c_angle_rad = math.radians(float(c_angle))
c_arc_ampl_rad = math.radians(float(c_arc_ampl))
# Cut outside the hall and cross the coupler slightly on the side
# mid angle between current cut position and coupler arc amplitude
half_arc = c_arc_ampl_rad / 2
cut_angle_offset = half_arc / 2 # Halfway between center and arc edge
cut_angle = c_angle_rad + cut_angle_offset # Offset to the side
# Cut from outside qubit through coupler to island center
# Start outside the qubit
outer_point = pya.DPoint(
(simulation.r_island + simulation.ground_gap + 15) * math.cos(cut_angle),
(simulation.r_island + simulation.ground_gap + 15) * math.sin(cut_angle),
)
# End at island edge
inner_point = pya.DPoint(
(simulation.r_island - 10) * math.cos(cut_angle), (simulation.r_island - 10) * math.sin(cut_angle)
)
cuts[f"{i}cplrmer"] = {
"p1": outer_point + simulation.refpoints["base"],
"p2": inner_point + simulation.refpoints["base"],
}
# Junction hall correction cut
squid_angle_rad = math.radians(simulation.squid_angle)
# Cut across the width of junction hall
hall_center = pya.DPoint(
(simulation.r_island + simulation.ground_gap / 2) * math.cos(squid_angle_rad),
(simulation.r_island + simulation.ground_gap / 2) * math.sin(squid_angle_rad),
)
# Perpendicular direction to junction hall
perp_angle = squid_angle_rad + math.pi / 2
cut_length = 15
p1 = pya.DPoint(
hall_center.x + cut_length * math.cos(perp_angle), hall_center.y + cut_length * math.sin(perp_angle)
)
p2 = pya.DPoint(
hall_center.x - cut_length * math.cos(perp_angle), hall_center.y - cut_length * math.sin(perp_angle)
)
cuts["leadsmer"] = {
"p1": p1 + simulation.refpoints["base"],
"p2": p2 + simulation.refpoints["base"],
"boundary_conditions": {"xmin": {"potential": 0}, "xmax": {"potential": 0}},
}
# Main island complement correction cut
# direction that avoids couplers and junction
# angle opposite to junction
complement_angle = math.radians(simulation.squid_angle + 180)
# Check if this angle conflicts with any coupler
min_angular_distance = 360
for c_angle in simulation.couplers_angle:
angular_dist = abs(float(c_angle) - (simulation.squid_angle + 180))
if angular_dist > 180:
angular_dist = 360 - angular_dist
min_angular_distance = min(min_angular_distance, angular_dist)
# Close to the coupler
if min_angular_distance < 30: # Less than 30 degrees separation
complement_angle = math.radians(simulation.squid_angle + 150)
# Cut from island to outside qubit
# points equidistant from the gap region
gap_distance = 10 # Same distance from gap as outer point
inner_point = pya.DPoint(
(simulation.r_island - gap_distance) * math.cos(complement_angle),
(simulation.r_island - gap_distance) * math.sin(complement_angle),
)
outer_point = pya.DPoint(
(simulation.r_island + simulation.ground_gap + gap_distance) * math.cos(complement_angle),
(simulation.r_island + simulation.ground_gap + gap_distance) * math.sin(complement_angle),
)
cuts[f"{simulation.face_ids[0]}complementmer"] = {
"p1": inner_point + simulation.refpoints["base"],
"p2": outer_point + simulation.refpoints["base"],
}
return cuts