def swap_rzz(theta: float, q0: ops.Qid, q1: ops.Qid) -> ops.OP_TREE:
"""
An implementation of SWAP * EXP(1j theta ZZ) using three sycamore gates.
This builds off of the zztheta method. A sycamore gate following the
zz-gate is a SWAP EXP(1j (THETA - pi/24) ZZ).
Args:
theta: exp(1j * theta )
q0: First qubit id to operate on
q1: Second qubit id to operate on
Returns:
The circuit that implements ZZ followed by a swap
"""
# Set interaction part.
circuit = circuits.Circuit()
angle_offset = np.pi / 24 - np.pi / 4
circuit.append(google.SYC(q0, q1))
circuit.append(rzz(theta - angle_offset, q0, q1))
# Get the intended circuit.
intended_circuit = circuits.Circuit(
ops.SWAP(q0, q1),
ops.ZZPowGate(exponent=2 * theta / np.pi,
global_shift=-0.5).on(q0, q1))
yield create_corrected_circuit(intended_circuit, circuit, q0, q1)
def operation_decomposer(
self, op: ops.Operation) -> Optional[list[ops.Operation]]:
# Decomposes CNOT and the CZPowGate family to Valkmusa native gates.
# All the decompositions below keep track of global phase (required for decomposing controlled gates).
if isinstance(op.gate, ops.CXPowGate) and op.gate.exponent == 1.0:
# CNOT is a special case, we decompose it using iSWAPs to be able to commute Z rotations through
control_qubit = op.qubits[0]
target_qubit = op.qubits[1]
s = op.gate.global_shift
iSWAP = ops.ISwapPowGate(exponent=1, global_shift=(s + 0.25) / 2)
return [
Lx.on(target_qubit),
Lzi.on(control_qubit),
Lz.on(target_qubit),
iSWAP.on(*op.qubits),
Lx.on(control_qubit),
iSWAP.on(*op.qubits),
Lz.on(target_qubit),
]
if isinstance(op.gate, ops.CZPowGate):
# decompose CZPowGate using ZZPowGate
t = op.gate.exponent
s = op.gate.global_shift
L = ops.rz(t / 2 * PI)
return [
ops.ZZPowGate(exponent=-0.5 * t,
global_shift=-2 * s - 1).on(*op.qubits),
L.on(op.qubits[0]),
L.on(op.qubits[1]),
]
if isinstance(op.gate, ops.ZZPowGate):
# ZZPowGate is decomposed using two applications of the XY interaction
t = op.gate.exponent
s = op.gate.global_shift
XY = ops.ISwapPowGate(exponent=-t, global_shift=-(s + 0.5) / 2)
return [
Lyi.on(op.qubits[0]),
Lyi.on(op.qubits[1]),
XY.on(*op.qubits),
ops.XPowGate(exponent=-1, global_shift=-0.5).on(op.qubits[0]),
XY.on(*op.qubits),
ops.XPowGate(exponent=1, global_shift=-0.5).on(op.qubits[0]),
Ly.on(op.qubits[0]),
Ly.on(op.qubits[1]),
]
if isinstance(op.gate, ops.ZPowGate):
# Rz using Rx, Ry
q = op.qubits[0]
return [
ops.XPowGate(exponent=-0.5).on(q),
ops.YPowGate(exponent=op.gate.exponent).on(q),
ops.XPowGate(exponent=0.5).on(q),
]
return None
def _translate_two_qubit_braket_instruction_to_cirq_operation(
instr: Instruction, ) -> List["cirq.Operation"]:
"""Converts the two-qubit braket instruction to Cirq.
Args:
instr: Two-qubit Braket instruction to convert.
Raises:
ValueError: If the instruction cannot be converted to Cirq.
"""
qubits = [LineQubit(int(qubit)) for qubit in instr.target]
gate = instr.operator
# Two-qubit non-parameterized gates.
if isinstance(gate, braket_gates.CNot):
return [cirq_ops.CNOT.on(*qubits)]
elif isinstance(gate, braket_gates.Swap):
return [cirq_ops.SWAP.on(*qubits)]
elif isinstance(gate, braket_gates.ISwap):
return [cirq_ops.ISWAP.on(*qubits)]
elif isinstance(gate, braket_gates.CZ):
return [cirq_ops.CZ.on(*qubits)]
elif isinstance(gate, braket_gates.CY):
return [
cirq_ops.S.on(qubits[1])**-1,
cirq_ops.CNOT.on(*qubits),
cirq_ops.S.on(qubits[1]),
]
# Two-qubit parameterized gates.
elif isinstance(gate, braket_gates.PSwap):
raise ValueError # TODO.
elif isinstance(gate, braket_gates.CPhaseShift):
return [cirq_ops.CZ.on(*qubits)**(gate.angle / np.pi)]
elif isinstance(gate, braket_gates.CPhaseShift00):
raise ValueError # TODO.
elif isinstance(gate, braket_gates.CPhaseShift01):
raise ValueError # TODO.
elif isinstance(gate, braket_gates.CPhaseShift10):
raise ValueError # TODO.
elif isinstance(gate, braket_gates.XX):
return [
cirq_ops.XXPowGate(exponent=gate.angle / np.pi,
global_shift=-0.5).on(*qubits)
]
elif isinstance(gate, braket_gates.YY):
return [
cirq_ops.YYPowGate(exponent=gate.angle / np.pi,
global_shift=-0.5).on(*qubits)
]
elif isinstance(gate, braket_gates.ZZ):
return [
cirq_ops.ZZPowGate(exponent=gate.angle / np.pi,
global_shift=-0.5).on(*qubits)
]
elif isinstance(gate, braket_gates.XY):
return [cirq_ops.ISwapPowGate(exponent=gate.angle / np.pi).on(*qubits)]
else:
raise ValueError(
f"Unable to convert the instruction {instr} to Cirq. If you think "
"this is a bug, you can open an issue on the Mitiq GitHub at "
"https://github.com/unitaryfund/mitiq.")
testing.assert_allclose_up_to_global_phase(
protocols.unitary(test_circuit),
protocols.unitary(cirq_circuit),
atol=1e-7,
)
@pytest.mark.parametrize(
"common_gate",
[
ops.CNOT,
ops.CZ,
ops.ISWAP,
ops.XXPowGate(exponent=-0.2),
ops.YYPowGate(exponent=0.3),
ops.ZZPowGate(exponent=-0.1),
],
)
def test_to_from_braket_common_two_qubit_gates(common_gate):
"""These gates should stay the same (i.e., not get decomposed) when
converting Cirq -> Braket -> Cirq.
"""
cirq_circuit = Circuit(common_gate.on(*LineQubit.range(2)))
test_circuit = from_braket(to_braket(cirq_circuit))
testing.assert_allclose_up_to_global_phase(
protocols.unitary(test_circuit),
protocols.unitary(cirq_circuit),
atol=1e-7,
)
# Cirq AAPowGate has a different global phase than braket AA which gets
def _translate_two_qubit_braket_instruction_to_cirq_operation(
instr: Instruction,
) -> List["cirq.Operation"]:
"""Converts the two-qubit braket instruction to Cirq.
Args:
instr: Two-qubit Braket instruction to convert.
Raises:
ValueError: If the instruction cannot be converted to Cirq.
"""
qubits = [LineQubit(int(qubit)) for qubit in instr.target]
gate = instr.operator
# Two-qubit non-parameterized gates.
if isinstance(gate, braket_gates.CNot):
return [cirq_ops.CNOT.on(*qubits)]
elif isinstance(gate, braket_gates.Swap):
return [cirq_ops.SWAP.on(*qubits)]
elif isinstance(gate, braket_gates.ISwap):
return [cirq_ops.ISWAP.on(*qubits)]
elif isinstance(gate, braket_gates.CZ):
return [cirq_ops.CZ.on(*qubits)]
elif isinstance(gate, braket_gates.CY):
return [
cirq_ops.S.on(qubits[1]) ** -1,
cirq_ops.CNOT.on(*qubits),
cirq_ops.S.on(qubits[1]),
]
# Two-qubit parameterized gates.
elif isinstance(gate, braket_gates.CPhaseShift):
return [cirq_ops.CZ.on(*qubits) ** (gate.angle / np.pi)]
elif isinstance(gate, braket_gates.CPhaseShift00):
return [
cirq_ops.XX(*qubits),
cirq_ops.CZ.on(*qubits) ** (gate.angle / np.pi),
cirq_ops.XX(*qubits),
]
elif isinstance(gate, braket_gates.CPhaseShift01):
return [
cirq_ops.X(qubits[0]),
cirq_ops.CZ.on(*qubits) ** (gate.angle / np.pi),
cirq_ops.X(qubits[0]),
]
elif isinstance(gate, braket_gates.CPhaseShift10):
return [
cirq_ops.X(qubits[1]),
cirq_ops.CZ.on(*qubits) ** (gate.angle / np.pi),
cirq_ops.X(qubits[1]),
]
elif isinstance(gate, braket_gates.PSwap):
return [
cirq_ops.SWAP.on(*qubits),
cirq_ops.CNOT.on(*qubits),
cirq_ops.Z.on(qubits[1]) ** (gate.angle / np.pi),
cirq_ops.CNOT.on(*qubits),
]
elif isinstance(gate, braket_gates.XX):
return [
cirq_ops.XXPowGate(
exponent=gate.angle / np.pi, global_shift=-0.5
).on(*qubits)
]
elif isinstance(gate, braket_gates.YY):
return [
cirq_ops.YYPowGate(
exponent=gate.angle / np.pi, global_shift=-0.5
).on(*qubits)
]
elif isinstance(gate, braket_gates.ZZ):
return [
cirq_ops.ZZPowGate(
exponent=gate.angle / np.pi, global_shift=-0.5
).on(*qubits)
]
elif isinstance(gate, braket_gates.XY):
return [cirq_ops.ISwapPowGate(exponent=gate.angle / np.pi).on(*qubits)]
else:
_raise_braket_to_cirq_error(instr)