workbench_algorithms.subroutines.trotterization

Qubricks for Trotterization.

TrotterStrategy

Bases: Protocol

Interface for applying unitary terms in Trotterization.

apply_trotter_terms

apply_trotter_terms(
    factor: int | float | complex,
    system: Qubits,
    reverse: bool = False,
    ctrl: Qubits | int = 0,
)

Method describing how to apply the terms in Trotterization, to be implemented in concrete implementations.

PauliSumTrotterStrategy

PauliSumTrotterStrategy(
    hamiltonian: PauliSum, trotter_order: int = None
)

Implementation of a TrotterStrategy for the simplest case of looping through Hamiltonian terms.

Parameters:

Name	Type	Description	Default
hamiltonian	PauliSum	PauliSum representation of the Hamiltonian to be Trotterized. The order of the terms in the PauliSum determines the order in which the Trotterized terms will be applied, with the coefficients determining their magnitude.	required
trotter_order	int	The order of the Trotterization.	None

apply_trotter_terms

apply_trotter_terms(
    factor, system, reverse: bool = False, ctrl: int = 0
)

Apply all the terms in the Hamiltonian, numerically or symbolically.

TrotterQuery

TrotterQuery(
    trotter_strategy: TrotterStrategy | None = None,
    trotter_order: int | None = None,
    hamiltonian: PauliSum | None = None,
    **kwargs,
)

Bases: Qubrick

Qubrick for implementing a Suzuki-Trotter approximation of an exponentiated Hamiltonian.

Parameters:

Name	Type	Description	Default
trotter_strategy	TrotterStrategy | None	A class that implements a TrotterStrategy for applying Trotter terms.	None
trotter_order	int	The order of Trotterization.	None
hamiltonian	PauliSum	The Hamiltonian expressed as a PauliSum.	None
**kwargs	dict[str, Any]	Other arguments to pass to the init.	{}

trotter_strategy property

trotter_strategy

Set the trotter_strategy property so it can't be modified.

compute

compute(
    system: Qubits,
    steps: int,
    evo_time: int,
    ctrl: Qubits | int = 0,
    trotter_order: int | None = None,
)

Execute the Suzuki-Trotter circuit.

Performs first and second order Trotterization directly. For higher orders, uses recursive calls to generate the appropriate product of operators.

Parameters:

Name	Type	Description	Default
system	Qubits	Qubits the Hamiltonian is acting on.	required
steps	int	The number of Trotter steps.	required
evo_time	int	(int): The total evolution time.	required
ctrl	(Qubits, int)	Qubit register to control evolution on. Defaults to 0.	0
trotter_order	int	The order of Trotterization. If not set, uses the Qubrick attribute self.trotter_order set at instantiation.	None