def get_supported_channels(): """A helper to get the channels that are supported in TFQ. Returns a dictionary mapping from supported channel types to number of qubits. """ # Add new channels here whenever additional support is needed. channel_mapping = dict() channel_mapping[cirq.DepolarizingChannel(0.01)] = 1 channel_mapping[cirq.AsymmetricDepolarizingChannel(0.01, 0.02, 0.03)] = 1 channel_mapping[cirq.GeneralizedAmplitudeDampingChannel(0.01, 0.02)] = 1 channel_mapping[cirq.AmplitudeDampingChannel(0.01)] = 1 channel_mapping[cirq.ResetChannel()] = 1 channel_mapping[cirq.PhaseDampingChannel(0.01)] = 1 channel_mapping[cirq.PhaseFlipChannel(0.01)] = 1 channel_mapping[cirq.BitFlipChannel(0.01)] = 1 return channel_mapping
def test_readout_error(): p00 = 0.05 p11 = 0.1 p = p11 / (p00 + p11) gamma = p11 / p # Create qubits and circuit qubits = [cirq.LineQubit(0), cirq.LineQubit(1)] circuit = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([cirq.H(qubits[1])]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), ) # Create noise model from NoiseProperties object with specified noise prop = NoiseProperties(p00=p00, p11=p11) noise_model = NoiseModelFromNoiseProperties(prop) noisy_circuit = cirq.Circuit(noise_model.noisy_moments(circuit, qubits)) # Insert expected channels to circuit expected_circuit = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([cirq.H(qubits[1])]), cirq.Moment([ cirq.GeneralizedAmplitudeDampingChannel( p=p, gamma=gamma).on_each(qubits) ]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), ) assert_equivalent_op_tree(expected_circuit, noisy_circuit) # Create Noise Model with just p00 prop_p00 = NoiseProperties(p00=p00) noise_model_p00 = NoiseModelFromNoiseProperties(prop_p00) noisy_circuit_p00 = cirq.Circuit( noise_model_p00.noisy_moments(circuit, qubits)) # Insert expected channels to circuit expected_circuit_p00 = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([cirq.H(qubits[1])]), cirq.Moment([ cirq.GeneralizedAmplitudeDampingChannel(p=0.0, gamma=p00).on_each(qubits) ]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), ) assert_equivalent_op_tree(expected_circuit_p00, noisy_circuit_p00) # Create Noise Model with just p11 prop_p11 = NoiseProperties(p11=p11) noise_model_p11 = NoiseModelFromNoiseProperties(prop_p11) noisy_circuit_p11 = cirq.Circuit( noise_model_p11.noisy_moments(circuit, qubits)) # Insert expected channels to circuit expected_circuit_p11 = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([cirq.H(qubits[1])]), cirq.Moment([ cirq.GeneralizedAmplitudeDampingChannel(p=1.0, gamma=p11).on_each(qubits) ]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), ) assert_equivalent_op_tree(expected_circuit_p11, noisy_circuit_p11)
def test_combined_error(): # Helper function to calculate pauli error from depolarization def pauli_error_from_depolarization(pauli_error, t1_ns, duration): t2 = 2 * t1_ns pauli_error_from_t1 = (1 - np.exp(-duration / t2)) / 2 + ( 1 - np.exp(-duration / t1_ns)) / 4 if pauli_error >= pauli_error_from_t1: return pauli_error - pauli_error_from_t1 return pauli_error t1_ns = 2000.0 p11 = 0.01 # Account for floating point errors # Needs Cirq issue 3965 to be resolved pauli_error = 0.019999999999999962 # Create qubits and circuit qubits = [cirq.LineQubit(0), cirq.LineQubit(1)] circuit = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([cirq.measure(qubits[0], key='q0')]), cirq.Moment([cirq.ISwapPowGate().on_each(qubits)]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), ) # Create noise model from NoiseProperties object with specified noise prop = NoiseProperties(t1_ns=t1_ns, p11=p11, pauli_error=pauli_error) noise_model = NoiseModelFromNoiseProperties(prop) with pytest.warns( RuntimeWarning, match='Pauli error from T1 decay is greater than total Pauli error' ): noisy_circuit = cirq.Circuit(noise_model.noisy_moments( circuit, qubits)) # Insert expected channels to circuit expected_circuit = cirq.Circuit( cirq.Moment([cirq.X(qubits[0])]), cirq.Moment([ cirq.depolarize( pauli_error_from_depolarization(pauli_error, t1_ns, 25.0) / 3).on_each(qubits) ]), cirq.Moment( [cirq.amplitude_damp(1 - np.exp(-25.0 / t1_ns)).on_each(qubits)]), cirq.Moment([cirq.CNOT(qubits[0], qubits[1])]), cirq.Moment([ cirq.depolarize( pauli_error_from_depolarization(pauli_error, t1_ns, 25.0) / 3).on_each(qubits) ]), cirq.Moment( [cirq.amplitude_damp(1 - np.exp(-25.0 / t1_ns)).on_each(qubits)]), cirq.Moment([ cirq.GeneralizedAmplitudeDampingChannel(p=1.0, gamma=p11).on(qubits[0]) ]), cirq.Moment([cirq.measure(qubits[0], key='q0')]), cirq.Moment([ cirq.depolarize( pauli_error_from_depolarization(pauli_error, t1_ns, 4000.0) / 3).on_each(qubits) ]), cirq.Moment([ cirq.amplitude_damp(1 - np.exp(-4000.0 / t1_ns)).on_each(qubits) ]), cirq.Moment([cirq.ISwapPowGate().on_each(qubits)]), cirq.Moment([ cirq.depolarize( pauli_error_from_depolarization(pauli_error, t1_ns, 32.0) / 3).on_each(qubits) ]), cirq.Moment( [cirq.amplitude_damp(1 - np.exp(-32.0 / t1_ns)).on_each(qubits)]), cirq.Moment([ cirq.GeneralizedAmplitudeDampingChannel(p=1.0, gamma=p11).on_each(qubits) ]), cirq.Moment([ cirq.measure(qubits[0], key='q0'), cirq.measure(qubits[1], key='q1') ]), cirq.Moment([ cirq.depolarize( pauli_error_from_depolarization(pauli_error, t1_ns, 4000.0) / 3).on_each(qubits) ]), cirq.Moment([ cirq.amplitude_damp(1 - np.exp(-4000.0 / t1_ns)).on_each(qubits) ]), ) assert_equivalent_op_tree(expected_circuit, noisy_circuit)
def test_generalized_amplitude_damping_repr(): cirq.testing.assert_equivalent_repr( cirq.GeneralizedAmplitudeDampingChannel(0.1, 0.3))
cirq.MutableDensePauliString('XXZZ', coefficient=-2), 'FREDKIN': cirq.FREDKIN, 'FSimGate': cirq.FSimGate(theta=0.123, phi=.456), 'Foxtail': cirq.google.Foxtail, 'GateOperation': [ cirq.CCNOT(*cirq.LineQubit.range(3)), cirq.CCZ(*cirq.LineQubit.range(3)), cirq.CNOT(*cirq.LineQubit.range(2)), cirq.CSWAP(*cirq.LineQubit.range(3)), cirq.CZ(*cirq.LineQubit.range(2)) ], 'GeneralizedAmplitudeDampingChannel': cirq.GeneralizedAmplitudeDampingChannel(0.1, 0.2), 'GlobalPhaseOperation': cirq.GlobalPhaseOperation(-1j), 'GridQubit': cirq.GridQubit(10, 11), 'H': cirq.H, 'HPowGate': [cirq.HPowGate(exponent=-8), cirq.H**0.123], 'I': cirq.I, 'ISWAP': cirq.ISWAP, 'ISwapPowGate': [cirq.ISwapPowGate(exponent=-8), cirq.ISWAP**0.123], 'IdentityGate': [ cirq.I, cirq.IdentityGate(num_qubits=5),