quri_parts.algo.mitigation.zne.zne module#

quri_parts.algo.mitigation.zne.zne.FoldingMethod#

Interface representing folding methods

alias of Callable[[NonParametricQuantumCircuit, float], list[int]]

quri_parts.algo.mitigation.zne.zne.ZeroExtrapolationMethod#

Interface representing zero noise extrapolation methods

alias of Callable[[Iterable[float], Iterable[float]], float]

quri_parts.algo.mitigation.zne.zne.CircuitScaling#

Interface representing scaling methods of circuit

alias of Callable[[NonParametricQuantumCircuit, float, Callable[[NonParametricQuantumCircuit, float], list[int]]], NonParametricQuantumCircuit]

quri_parts.algo.mitigation.zne.zne.create_folding_left() → Callable[[NonParametricQuantumCircuit, float], list[int]]#

Returns a FoldingMethod that gives a list of indices of gates to be folded.

Folding starts from the left of the circuit.

quri_parts.algo.mitigation.zne.zne.create_folding_right() → Callable[[NonParametricQuantumCircuit, float], list[int]]#

Returns a FoldingMethod that gives a list of indices of gates to be folded.

Folding starts from the right of the circuit.

quri_parts.algo.mitigation.zne.zne.create_folding_random(seed: int | None = None) → Callable[[NonParametricQuantumCircuit, float], list[int]]#

Returns a FoldingMethod that gives a list of indices of gates to be folded.

The gates to be folded are chosen at random.

Parameters:

seed – Seed for random number generator.

quri_parts.algo.mitigation.zne.zne.scaling_circuit_folding(circuit: NonParametricQuantumCircuit, scale_factor: float, folding_method: Callable[[NonParametricQuantumCircuit, float], list[int]]) → NonParametricQuantumCircuit#

Returns a scaled circuit. If the scale factor is odd, all gates are folded regardless of the folding method.

Parameters:

  • circuit – Circuit to be folded.

  • scale_factor – Factor to scale the circuit. A real number that satisfies >= 1.

  • folding_method – Folding method applied to the circuit as a FoldingMethod.

quri_parts.algo.mitigation.zne.zne.create_polynomial_extrapolate(order: int) → Callable[[Iterable[float], Iterable[float]], float]#

Returns a ZeroExtrapolationMethod that gives a zero-noise extrapolated value which is evaluated by using the polynomial fitting.

Parameters:

order – Order of the polynomial used for fitting.

quri_parts.algo.mitigation.zne.zne.create_exp_extrapolate(order: int) → Callable[[Iterable[float], Iterable[float]], float]#

Returns a ZeroExtrapolationMethod that gives a zero-noise extrapolated value which is evaluated by using the curve fitting and exponential ansatz f(x) = a + b exp(p(x)), where p(x) is a polynomial of a given order.

Parameters:

order – Order of the polynomial on the exponential used for fitting.

quri_parts.algo.mitigation.zne.zne.create_exp_extrapolate_with_const(order: int, constant: float) → Callable[[Iterable[float], Iterable[float]], float]#

Returns a ZeroExtrapolationMethod that gives a zero-noise extrapolated value which is evaluated by using the curve fitting and exponential ansatz f(x) = constant + b exp(p(x)), where p(x) is a polynomial of a given order and constant is a known parameter (obtained as the infinite-noise limit f(x->inf)).

Parameters:

  • order – Order of the polynomial on the exponential used for fitting.

  • constant – An infinite-noise limit parameter f(x->inf).

quri_parts.algo.mitigation.zne.zne.create_exp_extrapolate_with_const_log(order: int, constant: float) → Callable[[Iterable[float], Iterable[float]], float]#

Returns a ZeroExtrapolationMethod that gives a zero-noise extrapolated value which is evaluated by using the log fitting and exponential ansatz f(x) = constant + b exp(p(x)), where p(x) is a polynomial of a given order and constant is a known parameter (obtained as the infinite-noise limit f(x->inf)).

Parameters:

  • order – Order of the polynomial on the exponential used for fitting.

  • constant – An infinite-noise limit parameter f(x->inf).

quri_parts.algo.mitigation.zne.zne.zne(obs: Operator | PauliLabel, circuit: NonParametricQuantumCircuit, estimator: Callable[[Sequence[Operator | PauliLabel], Sequence[GeneralCircuitQuantumState]], Iterable[Estimate[complex]]], scale_factors: Iterable[float], extrapolate_method: Callable[[Iterable[float], Iterable[float]], float], folding_method: Callable[[NonParametricQuantumCircuit, float], list[int]]) → float#

Returns an error-mitigated expectation value of an observable by using zero-noise extrapolation (zne).

Parameters:

  • obs – Observable for which the expected value is calculated.

  • circuit – Circuit that ZNE is applied to.

  • estimator – An estimator that computes the expectation value from obs and circuit.

  • scale_factors – Factor to scale the circuit. An real number that satisfies >= 1.

  • extrapolate_method – ZeroExtrapolationMethod that determine the method of extrapolation.

  • folding_method – FoldingMethod that determines the method of folding.

quri_parts.algo.mitigation.zne.zne.richardson_extrapolation(obs: Operator | PauliLabel, circuit: NonParametricQuantumCircuit, estimator: Callable[[Sequence[Operator | PauliLabel], Sequence[GeneralCircuitQuantumState]], Iterable[Estimate[complex]]], scale_factors: Iterable[float], folding_method: Callable[[NonParametricQuantumCircuit, float], list[int]]) → float#

Returns an error-mitigated expectation value of an observable by using zne.

The order of polynomial = len(list(scale_factors)) - 1.

Parameters:

  • obs – Observable for which the expected value is calculated.

  • circuit – Circuit that apply zne.

  • estimator – An estimator that computes the expectation value from obs and circuit.

  • scale_factors – Factor to scale the circuit. A real number that satisfies >= 1.

  • folding_method – FoldingMethod that determines the method of folding.

quri_parts.algo.mitigation.zne.zne.create_zne_estimator(estimator: Callable[[Sequence[Operator | PauliLabel], Sequence[GeneralCircuitQuantumState]], Iterable[Estimate[complex]]], scale_factors: Iterable[float], extrapolate_method: Callable[[Iterable[float], Iterable[float]], float], folding_method: Callable[[NonParametricQuantumCircuit, float], list[int]]) → Callable[[Operator | PauliLabel, GeneralCircuitQuantumState], Estimate[complex]]#

Wrap the given ConcurrentQuantumEstimator to create a QuantumEstimator where zero-noise mitigation is automatically applied to the result.

Parameters:

  • estimator – An estimator that computes the expectation value from obs and circuit.

  • scale_factors – Factor to scale the circuit. A real number that satisfies >= 1.

  • extrapolate_method – ZeroExtrapolationMethod that determine the method of extrapolation.

  • folding_method – FoldingMethod that determines the method of folding.