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Coherence stabilization of a two-qubit gate by AC fields

Karen M. Fonseca Romero·Sigmund Kohler·Peter Hänggi
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Abstract

We consider a CNOT gate operation under the influence of quantum bit-flip noise and demonstrate that ac fields can change bit-flip noise into phase noise and thereby improve coherence up to several orders of magnitude while the gate operation time remains unchanged. Within a high-frequency approximation, both purity and fidelity of the gate operation are studied analytically. The numerical treatment with a Bloch-Redfield master equation confirms the analytical results.

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Karen M. Fonseca Romero, Sigmund Kohler, Peter Hänggi. 2004-09-30. Coherence stabilization of a two-qubit gate by AC fields. https://doi.org/10.1103/physrevlett.95.140502

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