from ..layouts.layout import Layout
from ..layouts.operations import check_overlap_layouts
[docs]
def set_x(layout: Layout) -> None:
"""Adds the required attributes (in place) for the layout to run the Pauli X
gate for the unrotated surface code.
Parameters
----------
layout
The layout in which to add the attributes.
"""
if len(layout.logical_qubits) != 1:
raise ValueError(
"The given surface code does not have a logical qubit, "
f"it has {len(layout.logical_qubits)}."
)
data_qubits = layout.data_qubits
anc_qubits = layout.anc_qubits
log_qubit_label = layout.logical_qubits[0]
gate_label = f"log_x_{log_qubit_label}"
x_gates = {q: "I" for q in data_qubits}
for q in layout.logical_param("log_x", log_qubit_label):
x_gates[q] = "X"
# Store logical gate information to the data qubits
for qubit in data_qubits:
layout.set_param(gate_label, qubit, {"local": x_gates[qubit]})
# Store new stabilizer generators to the ancilla qubits
for anc_qubit in anc_qubits:
layout.set_param(
gate_label,
anc_qubit,
{"new_stab_gen": [anc_qubit], "new_stab_gen_inv": [anc_qubit]},
)
return
[docs]
def set_z(layout: Layout) -> None:
"""Adds the required attributes (in place) for the layout to run the Pauli Z
gate for the unrotated surface code.
Parameters
----------
layout
The layout in which to add the attributes.
"""
if len(layout.logical_qubits) != 1:
raise ValueError(
"The given surface code does not have a logical qubit, "
f"it has {len(layout.logical_qubits)}."
)
data_qubits = layout.data_qubits
anc_qubits = layout.anc_qubits
log_qubit_label = layout.logical_qubits[0]
gate_label = f"log_z_{log_qubit_label}"
z_gates = {q: "I" for q in data_qubits}
for q in layout.logical_param("log_z", log_qubit_label):
z_gates[q] = "Z"
# Store logical gate information to the data qubits
for qubit in data_qubits:
layout.set_param(gate_label, qubit, {"local": z_gates[qubit]})
# Store new stabilizer generators to the ancilla qubits
for anc_qubit in anc_qubits:
layout.set_param(
gate_label,
anc_qubit,
{"new_stab_gen": [anc_qubit], "new_stab_gen_inv": [anc_qubit]},
)
return
[docs]
def set_idle(layout: Layout) -> None:
"""Adds the required attributes (in place) for the layout to run the Pauli I
gate for codes with just one logical qubit.
Parameters
----------
layout
The layout in which to add the attributes.
"""
if len(layout.logical_qubits) != 1:
raise ValueError(
"The given surface code does not have a logical qubit, "
f"it has {len(layout.logical_qubits)}."
)
data_qubits = layout.data_qubits
anc_qubits = layout.anc_qubits
log_qubit_label = layout.logical_qubits[0]
gate_label = f"idle_{log_qubit_label}"
# Store logical gate information to the data qubits
for qubit in data_qubits:
layout.set_param(gate_label, qubit, {"local": "I"})
# Store new stabilizer generators to the ancilla qubits
for anc_qubit in anc_qubits:
layout.set_param(
gate_label,
anc_qubit,
{"new_stab_gen": [anc_qubit], "new_stab_gen_inv": [anc_qubit]},
)
return
[docs]
def set_trans_cnot(layout_c: Layout, layout_t: Layout) -> None:
"""Adds the required attributes (in place) for the layout to run the
transversal CNOT gate for the unrotated surface code.
Parameters
----------
layout_c
The layout for the control of the CNOT for which to add the attributes.
layout_t
The layout for the target of the CNOT for which to add the attributes.
"""
if (layout_c.code not in ["unrotated_surface_code", "rotated_surface_code"]) or (
layout_t.code not in ["unrotated_surface_code", "rotated_surface_code"]
):
raise ValueError(
"This function is for unrotated and rotated surface codes, "
f"but layouts for {layout_t.code} and {layout_c.code} were given."
)
if (layout_c.distance_x != layout_t.distance_x) or (
layout_c.distance_z != layout_t.distance_z
):
raise ValueError("This function requires two surface codes of the same size.")
check_overlap_layouts(layout_c, layout_t)
gate_label = (
f"log_trans_cnot_{layout_c.logical_qubits[0]}_{layout_t.logical_qubits[0]}"
)
qubit_coords_c = layout_c.qubit_coords
qubit_coords_t = layout_t.qubit_coords
bottom_left_qubit_c = sorted(
qubit_coords_c.items(), key=lambda x: 999_999_999 * x[1][0] + x[1][1]
)
bottom_left_qubit_t = sorted(
qubit_coords_t.items(), key=lambda x: 999_999_999 * x[1][0] + x[1][1]
)
mapping_t_to_c = {}
mapping_c_to_t = {}
for (qc, _), (qt, _) in zip(bottom_left_qubit_c, bottom_left_qubit_t):
mapping_t_to_c[qt] = qc
mapping_c_to_t[qc] = qt
# Store the logical information for the data qubits
data_qubits_c = set(layout_c.data_qubits)
data_qubits_t = set(layout_t.data_qubits)
for qubit in data_qubits_c:
layout_c.set_param(
gate_label, qubit, {"cz": mapping_c_to_t[qubit], "local": "I"}
)
for qubit in data_qubits_t:
layout_t.set_param(
gate_label, qubit, {"cz": mapping_t_to_c[qubit], "local": "H"}
)
# Compute the new stabilizer generators based on the CNOT connections
anc_to_new_stab = {}
for anc in layout_c.get_qubits(role="anc", stab_type="z_type"):
anc_to_new_stab[anc] = [anc]
for anc in layout_c.get_qubits(role="anc", stab_type="x_type"):
anc_to_new_stab[anc] = [anc, mapping_c_to_t[anc]]
for anc in layout_t.get_qubits(role="anc", stab_type="z_type"):
anc_to_new_stab[anc] = [anc, mapping_t_to_c[anc]]
for anc in layout_t.get_qubits(role="anc", stab_type="x_type"):
anc_to_new_stab[anc] = [anc]
# Store new stabilizer generators to the ancilla qubits
# CNOT^\dagger = CNOT
for anc in layout_c.anc_qubits:
layout_c.set_param(
gate_label,
anc,
{
"new_stab_gen": anc_to_new_stab[anc],
"new_stab_gen_inv": anc_to_new_stab[anc],
},
)
for anc in layout_t.anc_qubits:
layout_t.set_param(
gate_label,
anc,
{
"new_stab_gen": anc_to_new_stab[anc],
"new_stab_gen_inv": anc_to_new_stab[anc],
},
)
return
