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Natural two-qubit gate for quantum computation using the XY interaction

Norbert Schuch·Jens Siewert
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Abstract

The two-qubit interaction Hamiltonian of a given physical implementation determines whether or not a two-qubit gate such as the CNOT gate can be realized easily. It can be shown that, e.g., with the XY interaction more than one two-qubit operation is required in order to realize CNOT. Here we propose a two-qubit gate for the XY interaction which combines CNOT with the SWAP operation. By using this gate quantum circuits can be implemented efficiently, even if only nearest-neighbor coupling between the qubits is available.

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Norbert Schuch, Jens Siewert. 2002-09-04. Natural two-qubit gate for quantum computation using the XY interaction. https://doi.org/10.1103/physreva.67.032301

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