tk_to_qiskit: Support of Qiskit.QuantumCircuit.Layout Attribute

[nquetschlich]

Hello,

in Qiskit v0.43.0 (Link: https://qiskit.org/documentation/locale/de_DE/release_notes.html#:~:text=Added%20a%20new%20attribute%2C%20layout), the layout attribute is officially introduced that stores a TranspileLayout to preserve mapping information of a compiled and mapped quantum circuit (e.g., initial_layout, input_qubit_mapping, final_layout).

I was wondering whether it is planned that pytket-qiskit's tk_to_qiskit supports/sets this attribute when transforming a quantum circuit mapped using pytket to a qiskit circuit.

[CalMacCQ]

Hi,

Interesting, I wasn't aware of this feature in qiskit until you mentioned it.

So just to clarify this would allow a circuit to be mapped/routed in pytket and then the layout information is stored as stored as an attribute in the qiskit QuantumCircuit returned by tk_to_qiskit ?

Would you find this feature useful?

[nquetschlich]

Hi,

Interesting, I wasn't aware of this feature in qiskit until you mentioned it.

So just to clarify this would allow a circuit to be mapped/routed in pytket and then the layout information is stored as stored as an attribute in the qiskit QuantumCircuit returned by tk_to_qiskit ?

Would you find this fetaure useful?

Yes, that would be helpful to know after the compilation which logical qubit was initially assigned to which physical qubit. And ideally, also for the final outcome after considering necessary SWAP gates introduced during compilation to match a given device's connectivity.