qiskit.algorithms.HamiltonianPhaseEstimation.estimate

HamiltonianPhaseEstimation.estimate(hamiltonian, state_preparation=None, evolution=None, bound=None)

Run the Hamiltonian phase estimation algorithm.

Parameters

• hamiltonian (PauliOp | MatrixOp | SummedOp | Pauli | SparsePauliOp | PauliSumOp) – A Hermitian operator. If the algorithm is used with a Sampler primitive, the allowed types are Pauli, SparsePauliOp, and PauliSumOp. If the algorithm is used with a QuantumInstance, PauliOp, ``MatrixOp, PauliSumOp, and SummedOp types are allowed.

• state_preparation (StateFn | QuantumCircuit | Statevector | None) – The StateFn to be prepared, whose eigenphase will be measured. If this parameter is omitted, no preparation circuit will be run and input state will be the all-zero state in the computational basis.

• evolution (EvolutionSynthesis | EvolutionBase | None) – An evolution converter that generates a unitary from hamiltonian. If None, then the default PauliTrotterEvolution is used.

• bound (float | None) – An upper bound on the absolute value of the eigenvalues of hamiltonian. If omitted, then hamiltonian must be a Pauli sum, or a PauliOp, in which case a bound will be computed. If hamiltonian is a MatrixOp, then bound may not be None. The tighter the bound, the higher the resolution of computed phases.

Returns

HamiltonianPhaseEstimationResult instance containing the result of the estimation and diagnostic information.

Raises

• TypeError – If evolution is not of type EvolutionSynthesis when a Sampler is provided.

• TypeError – If hamiltonian type is not Pauli or SparsePauliOp or PauliSumOp when a Sampler is provided.

• ValueError – If bound is None and hamiltonian is not a Pauli sum, i.e. a PauliSumOp or a SummedOp whose terms are of type PauliOp.

• TypeError – If evolution is not of type EvolutionBase when no Sampler is provided.

Return type

HamiltonianPhaseEstimationResult