def circuit_from_qasm(qasm: str) -> cirq.circuits.Circuit:
"""Parses an OpenQASM 2.0 program to a Cirq circuit.
The OpenQASM language has been extended by the ``ising``, ``xy``, ``iswap`` and ``sqrt_iswap`` gates.
Args:
qasm: OpenQASM string
Returns:
parsed circuit
"""
parser = QasmParser()
parser.all_gates['ising'] = QasmGateStatement(
qasm_gate='ising',
cirq_gate=lambda params: ig.IsingGate(exponent=params[0]),
num_params=1,
num_args=2)
parser.all_gates['xy'] = QasmGateStatement(
qasm_gate='xy',
cirq_gate=lambda params: ig.XYGate(exponent=params[0]),
num_params=1,
num_args=2)
parser.all_gates['iswap'] = QasmGateStatement(qasm_gate='iswap',
cirq_gate=cirq.ops.ISWAP,
num_params=0,
num_args=2)
parser.all_gates['sqrt_iswap'] = QasmGateStatement(
qasm_gate='sqrt_iswap',
cirq_gate=cirq.ops.ISwapPowGate(exponent=0.5),
num_params=0,
num_args=2)
return parser.parse(qasm).circuit
def operation_decomposer(self, op: ops.Operation):
"""Decomposes CNOT and the CZPowGate family to Valkmusa native 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]
iSWAP = ig.XYGate(exponent=-1 / 2)
return [
ops.XPowGate(exponent=0.5).on(target_qubit),
ops.ZPowGate(exponent=-0.5).on(control_qubit),
ops.ZPowGate(exponent=0.5).on(target_qubit),
iSWAP.on(*op.qubits),
ops.XPowGate(exponent=0.5).on(control_qubit),
iSWAP.on(*op.qubits),
ops.ZPowGate(exponent=0.5).on(target_qubit),
]
if isinstance(op.gate, ops.CZPowGate):
# the CZ family is decomposed using two applications of the XY interaction
s = -op.gate.exponent / 4
r = -2 * s
return [
ops.XPowGate(exponent=0.5).on(op.qubits[0]),
ops.YPowGate(exponent=-0.5).on(op.qubits[1]),
ops.ZPowGate(exponent=0.5).on(op.qubits[1]),
ig.XYGate(exponent=s).on(*op.qubits),
ops.YPowGate(exponent=1).on(op.qubits[1]),
ig.XYGate(exponent=s).on(*op.qubits),
ops.XPowGate(exponent=-0.5).on(op.qubits[0]),
ops.YPowGate(exponent=0.5).on(op.qubits[1]),
ops.XPowGate(exponent=-0.5).on(op.qubits[1]),
ops.ZPowGate(exponent=r).on(op.qubits[0]),
ops.ZPowGate(exponent=r + 1).on(op.qubits[1]),
]
if isinstance(op.gate, ops.ISwapPowGate):
# the ISwap family is implemented using the XY interaction
return [ig.XYGate(exponent=-0.5 * op.gate.exponent).on(*op.qubits)]
return None
def operation_decomposer(self, op):
"""Decomposes gates into the native Adonis gate set.
For now provides a special decomposition for CZPowGate only, which seems to be enough.
"""
if isinstance(op.gate, ops.CZPowGate):
# decompose CZPowGate using IsingGate
s = 1 - op.gate.exponent / 2
G = ig.IsingGate(exponent=s)
# local Z rotations
L = ops.ZPowGate(exponent=-s)
return [G.on(*op.qubits), L.on(op.qubits[0]), L.on(op.qubits[1])]
if isinstance(op.gate, ops.ISwapPowGate):
# the ISwap family is implemented using the XY interaction
return [ig.XYGate(exponent=-0.5 * op.gate.exponent).on(*op.qubits)]
return None
native_1q_gates = [
cirq.X,
cirq.Y,
cirq.XPowGate(exponent=0.23),
cirq.YPowGate(exponent=0.71),
cirq.PhasedXPowGate(phase_exponent=1.7, exponent=-0.58),
cirq.Z,
cirq.ZPowGate(exponent=-0.23),
]
finally_decomposed_1q_gates = []
native_2q_gates = [
ig.IsingGate(exponent=0.45),
ig.XYGate(exponent=0.38),
]
non_native_1q_gates = [
cirq.H,
cirq.HPowGate(exponent=-0.55),
cirq.PhasedXZGate(x_exponent=0.2,
z_exponent=-0.5,
axis_phase_exponent=0.75),
]
non_native_2q_gates = [
cirq.ISwapPowGate(exponent=0.27),
cirq.ISWAP,
cirq.SWAP,
cirq.CNOT,
def test_gate_matrices_xy(self, t):
"""Verify that the XY gates work as expected."""
U = cirq.ISwapPowGate(exponent=t)._unitary_()
assert np.allclose(ig.XYGate(exponent=-0.5 * t)._unitary_(), U)