def test_phase_calibrated_fsim_gate_compensated(phase_exponent: float):
a, b = cirq.LineQubit.range(2)
ideal_gate = cirq.FSimGate(theta=np.pi / 4, phi=0.0)
characterized_gate = cirq.PhasedFSimGate(theta=ideal_gate.theta,
zeta=0.1,
chi=0.2,
gamma=0.3,
phi=ideal_gate.phi)
parameters = PhasedFSimCharacterization(
theta=ideal_gate.theta,
zeta=characterized_gate.zeta,
chi=characterized_gate.chi,
gamma=characterized_gate.gamma,
phi=ideal_gate.phi,
)
calibrated = PhaseCalibratedFSimGate(ideal_gate,
phase_exponent=phase_exponent)
# Passing characterized_gate as engine_gate simulates the hardware execution.
operations = calibrated.with_zeta_chi_gamma_compensated(
(a, b), parameters, engine_gate=characterized_gate)
cirq.testing.assert_allclose_up_to_global_phase(
cirq.unitary(cirq.Circuit(operations)),
cirq.unitary(
cirq.Circuit([
[cirq.Z(a)**-phase_exponent,
cirq.Z(b)**phase_exponent],
ideal_gate.on(a, b),
[cirq.Z(a)**phase_exponent,
cirq.Z(b)**-phase_exponent],
])),
atol=1e-8,
)
def from_characterization(
cls,
qubits: Tuple[Qid, Qid],
gate_calibration: PhaseCalibratedFSimGate,
parameters: PhasedFSimCharacterization,
characterization_index: Optional[int],
) -> 'FSimPhaseCorrections':
"""Creates an operation that compensates for zeta, chi and gamma angles of the supplied
gate and characterization.
Args:
qubits: Qubits that the gate should act on.
gate_calibration: Original, imperfect gate that is supposed to run on the hardware
together with phase information.
parameters: The real parameters of the supplied gate.
characterization_index: characterization index to use at each moment with gate.
"""
operations = gate_calibration.with_zeta_chi_gamma_compensated(
qubits, parameters)
moment_to_calibration = [None, characterization_index, None]
return cls(operations, moment_to_calibration)
