convert_to_cz#

convert_to_cz(strict: bool = False) → Callable[[QuantumCircuit], QuantumCircuit][source]#

Create a pass that converts two-qubit gates to CZ-based decompositions.

This pass converts CX (CNOT), CY, and SWAP gates to their CZ-based equivalents using single-qubit gate decompositions. CZ gates are native to many superconducting quantum computers.

Two-qubit gates that are already CZ or barrier instructions are always left unchanged. Any other two-qubit gate that has no known CZ decomposition is either passed through silently (strict=False, the default) or causes the pass to raise an exception (strict=True).

Note

This pass does not decompose composite (wrapped) gates. Use the decompose() pass to expand composite gates into elementary operations before applying this pass.

Parameters:

strictbool, optional: When True, an Exception is raised if a two-qubit gate with no known CZ decomposition is encountered. When False (the default), such gates are left unchanged in the output circuit.

Returns:

Callable[[QuantumCircuit], QuantumCircuit]: A pass function suitable for PassManager.add_pass().

Examples

Convert a CX gate to H—CZ—H:

>>> from qrisp import QuantumCircuit, PassManager
>>> from qrisp import convert_to_cz
>>> qc = QuantumCircuit(2)
>>> qc.cx(0, 1)
>>> print(qc)

qb_69: ──■──
       ┌─┴─┐
qb_70: ┤ X ├
       └───┘
>>> pm = PassManager()
>>> pm += convert_to_cz()
>>> optimized_qc = pm.run(qc)
>>> print(optimized_qc)
qb_69: ──────■──────
       ┌───┐ │ ┌───┐
qb_70: ┤ H ├─■─┤ H ├
       └───┘   └───┘