class qiskit.algorithms.TrotterQRTE(product_formula=None, expectation=None, quantum_instance=None)[source]#

Bases: RealEvolver

Deprecated: Quantum Real Time Evolution using Trotterization.

The TrotterQRTE class has been superseded by the qiskit.algorithms.time_evolvers.trotterization.TrotterQRTE class. This class will be deprecated in a future release and subsequently removed after that.

Type of Trotterization is defined by a ProductFormula provided.


from qiskit.opflow import X, Z, Zero
from qiskit.algorithms import EvolutionProblem, TrotterQRTE
from qiskit import BasicAer
from qiskit.utils import QuantumInstance

operator = X + Z
initial_state = Zero
time = 1
evolution_problem = EvolutionProblem(operator, 1, initial_state)
# LieTrotter with 1 rep
backend = BasicAer.get_backend("statevector_simulator")
quantum_instance = QuantumInstance(backend=backend)
trotter_qrte = TrotterQRTE(quantum_instance=quantum_instance)
evolved_state = trotter_qrte.evolve(evolution_problem).evolved_state

Deprecated since version 0.24.0: The class qiskit.algorithms.evolvers.trotterization.trotter_qrte.TrotterQRTE is deprecated as of qiskit-terra 0.24.0. It will be removed no earlier than 3 months after the release date. Instead, use the class qiskit.algorithms.time_evolvers.trotterization.TrotterQRTE. See for a migration guide.

  • product_formula (ProductFormula | None) – A Lie-Trotter-Suzuki product formula. The default is the Lie-Trotter first order product formula with a single repetition.

  • expectation (ExpectationBase | None) – An instance of ExpectationBase which defines a method for calculating expectation values of EvolutionProblem.aux_operators.

  • quantum_instance (QuantumInstance | Backend | None) – A quantum instance used for calculating expectation values of EvolutionProblem.aux_operators.



Returns an expectation used in the algorithm.


Returns a product formula used in the algorithm.


Returns a quantum instance used in the algorithm.



Evolves a quantum state for a given time using the Trotterization method based on a product formula provided. The result is provided in the form of a quantum circuit. If auxiliary operators are included in the evolution_problem, they are evaluated on an evolved state using a backend provided.


Time-dependent Hamiltonians are not yet supported.


evolution_problem (EvolutionProblem) – Instance defining evolution problem. For the included Hamiltonian, PauliOp, SummedOp or PauliSumOp are supported by TrotterQRTE.


Evolution result that includes an evolved state as a quantum circuit and, optionally, auxiliary operators evaluated for a resulting state on a backend.

  • ValueError – If t_param is not set to None in the EvolutionProblem (feature not currently supported).

  • ValueError – If the initial_state is not provided in the EvolutionProblem.

Return type:


classmethod supports_aux_operators()[source]#

Whether computing the expectation value of auxiliary operators is supported.


True if aux_operators expectations in the EvolutionProblem can be evaluated, False


Return type: