Source code for kqcircuits.qubits.double_pads_splines

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from kqcircuits.util.geometry_helper import bspline_points
from kqcircuits.util.parameters import Param, pdt
from kqcircuits.qubits.double_pads import DoublePads
from kqcircuits.pya_resolver import pya


[docs] class DoublePadsSplines(DoublePads): """A two-island qubit, consisting of two spline-constructed islands shunted by a junction, with one capacitive coupler. Contains a coupler on the north edge and two separate qubit islands in the center joined by a junction or SQUID loaded from another library. Refpoint for a readout line at the opening to the coupler and a modifiable refpoint for a driveline outside of the rectangle. """ island_spline = Param( pdt.TypeList, "Control points of a B-Spline that defines left half of the island", [-250, 20, -250, 80, -100, 100, 0, 100], ) island_spline_samples = Param( pdt.TypeInt, "Number of samples taken from each island spline", 100, docstring=( "Number of samples taken from each island spline. " "There is a spline for each consequent series of four control points" ), ) def _build_island1(self, squid_height, taper_height): island1_bottom = self.squid_offset + squid_height / 2 curve_start = pya.DPoint(0, island1_bottom + taper_height) island1_control_points = [curve_start + pya.DPoint(-self.island1_taper_width / 2, 0)] + [ curve_start + pya.DPoint(float(self.island_spline[idx]), float(self.island_spline[idx + 1])) for idx in range(0, len(self.island_spline), 2) ] island1_control_points += [pya.DPoint(-p.x, p.y) for p in reversed(island1_control_points[:-1])] for i, p in enumerate(island1_control_points): self.refpoints[f"island1_control_point_{i}"] = p island1_polygon = pya.DPolygon( bspline_points(island1_control_points, self.island_spline_samples, startpoint=True, endpoint=True) ) island1_region = pya.Region(island1_polygon.to_itype(self.layout.dbu)) island1_taper = pya.Region( pya.DPolygon( [ # pertrude taper into island in case of precision errors pya.DPoint(self.island1_taper_width / 2, island1_bottom + taper_height + 1), pya.DPoint(self.island1_taper_width / 2, island1_bottom + taper_height), pya.DPoint(self.island1_taper_junction_width / 2, island1_bottom), pya.DPoint(-self.island1_taper_junction_width / 2, island1_bottom), pya.DPoint(-self.island1_taper_width / 2, island1_bottom + taper_height), # pertrude taper into island in case of precision errors pya.DPoint(-self.island1_taper_width / 2, island1_bottom + taper_height + 1), ] ).to_itype(self.layout.dbu) ) return island1_region + island1_taper def _build_island2(self, squid_height, taper_height): island2_top = self.squid_offset - squid_height / 2 curve_start = pya.DPoint(0, island2_top - taper_height) island2_control_points = [curve_start + pya.DPoint(-self.island2_taper_width / 2, 0)] + [ curve_start + pya.DPoint(float(self.island_spline[idx]), -float(self.island_spline[idx + 1])) for idx in range(0, len(self.island_spline), 2) ] island2_control_points += [pya.DPoint(-p.x, p.y) for p in reversed(island2_control_points[:-1])] for i, p in enumerate(island2_control_points): self.refpoints[f"island2_control_point_{i}"] = p island2_polygon = pya.DPolygon( bspline_points(island2_control_points, self.island_spline_samples, startpoint=True, endpoint=True) ) island2_region = pya.Region(island2_polygon.to_itype(self.layout.dbu)) island2_taper = pya.Region( pya.DPolygon( [ # pertrude taper into island in case of precision errors pya.DPoint(self.island2_taper_width / 2, island2_top - taper_height - 1), pya.DPoint(self.island2_taper_width / 2, island2_top - taper_height), pya.DPoint(self.island2_taper_junction_width / 2, island2_top), pya.DPoint(-self.island2_taper_junction_width / 2, island2_top), pya.DPoint(-self.island2_taper_width / 2, island2_top - taper_height), # pertrude taper into island in case of precision errors pya.DPoint(-self.island2_taper_width / 2, island2_top - taper_height - 1), ] ).to_itype(self.layout.dbu) ) return island2_region + island2_taper