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---
title: SuzukiTrotter
description: API reference for qiskit.synthesis.SuzukiTrotter
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit.synthesis.SuzukiTrotter
---
# SuzukiTrotter
<Class id="qiskit.synthesis.SuzukiTrotter" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.25/qiskit/synthesis/evolution/suzuki_trotter.py" signature="qiskit.synthesis.SuzukiTrotter(order=2, reps=1, insert_barriers=False, cx_structure='chain', atomic_evolution=None)" modifiers="class">
Bases: [`ProductFormula`](qiskit.synthesis.ProductFormula "qiskit.synthesis.evolution.product_formula.ProductFormula")
The (higher order) Suzuki-Trotter product formula.
The Suzuki-Trotter formulas improve the error of the Lie-Trotter approximation. For example, the second order decomposition is
$$
e^{A + B} \approx e^{B/2} e^{A} e^{B/2}.
$$
Higher order decompositions are based on recursions, see Ref. \[1] for more details.
In this implementation, the operators are provided as sum terms of a Pauli operator. For example, in the second order Suzuki-Trotter decomposition we approximate
$$
e^{-it(XX + ZZ)} = e^{-it/2 ZZ}e^{-it XX}e^{-it/2 ZZ} + \mathcal{O}(t^3).
$$
**References**
\[1]: D. Berry, G. Ahokas, R. Cleve and B. Sanders, “Efficient quantum algorithms for simulating sparse Hamiltonians” (2006). [arXiv:quant-ph/0508139](https://arxiv.org/abs/quant-ph/0508139) \[2]: N. Hatano and M. Suzuki, “Finding Exponential Product Formulas of Higher Orders” (2005). [arXiv:math-ph/0506007](https://arxiv.org/pdf/math-ph/0506007.pdf)
<Admonition title="Deprecated since version 0.20.0" type="danger">
Setting order to an odd number in the constructor of SuzukiTrotter is deprecated as of qiskit-terra 0.20.0. It will be removed no earlier than 3 months after the release date. Suzuki product formulae are symmetric and therefore only defined for even orders.
</Admonition>
**Parameters**
* **order** ([*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)")) The order of the product formula.
* **reps** ([*int*](https://docs.python.org/3/library/functions.html#int "(in Python v3.12)")) The number of time steps.
* **insert\_barriers** ([*bool*](https://docs.python.org/3/library/functions.html#bool "(in Python v3.12)")) Whether to insert barriers between the atomic evolutions.
* **cx\_structure** ([*str*](https://docs.python.org/3/library/stdtypes.html#str "(in Python v3.12)")) How to arrange the CX gates for the Pauli evolutions, can be “chain”, where next neighbor connections are used, or “fountain”, where all qubits are connected to one.
* **atomic\_evolution** ([*Callable*](https://docs.python.org/3/library/typing.html#typing.Callable "(in Python v3.12)")*\[\[*[*Pauli*](qiskit.quantum_info.Pauli "qiskit.quantum_info.operators.symplectic.pauli.Pauli") *|*[*SparsePauliOp*](qiskit.quantum_info.SparsePauliOp "qiskit.quantum_info.operators.symplectic.sparse_pauli_op.SparsePauliOp")*,* [*float*](https://docs.python.org/3/library/functions.html#float "(in Python v3.12)")*],* [*QuantumCircuit*](qiskit.circuit.QuantumCircuit "qiskit.circuit.quantumcircuit.QuantumCircuit")*] | None*) A function to construct the circuit for the evolution of single Pauli string. Per default, a single Pauli evolution is decomposed in a CX chain and a single qubit Z rotation.
## Attributes
### settings
<Attribute id="qiskit.synthesis.SuzukiTrotter.settings">
Return the settings in a dictionary, which can be used to reconstruct the object.
**Returns**
A dictionary containing the settings of this product formula.
**Raises**
[**NotImplementedError**](https://docs.python.org/3/library/exceptions.html#NotImplementedError "(in Python v3.12)") If a custom atomic evolution is set, which cannot be serialized.
</Attribute>
## Methods
### synthesize
<Function id="qiskit.synthesis.SuzukiTrotter.synthesize" signature="synthesize(evolution)">
Synthesize an `qiskit.circuit.library.PauliEvolutionGate`.
**Parameters**
**evolution** ([*PauliEvolutionGate*](qiskit.circuit.library.PauliEvolutionGate "qiskit.circuit.library.PauliEvolutionGate")) The evolution gate to synthesize.
**Returns**
A circuit implementing the evolution.
**Return type**
[QuantumCircuit](qiskit.circuit.QuantumCircuit "qiskit.circuit.QuantumCircuit")
</Function>
</Class>