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arXiv · 2110.02092

Universal deterministic quantum operations in microwave quantum links

Guillermo F. Peñas·Ricardo Puebla·Tomás Ramos·Peter Rabl·Juan José García-Ripoll
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Abstract

We propose a realistic setup, inspired by already existing experiments, within which we develop a general formalism for the implementation of distributed quantum gates. Mediated by a quantum link that establishes a bidirectional quantum channel between distant nodes, our proposal works both for inter- and intra node communication and handles scenarios ranging from the few to the many modes limit of the quantum link. We are able to design fast and reliable state transfer protocols in every regime of operation, which, together with a detailed description of the scattering process, allows us to engineer two sets of deterministic universal distributed quantum gates. Gates whose implementation in quantum networks does not need entanglement distribution nor measurements. By employing a realistic description of the physical setup we identify the most relevant imperfections in the quantum links as well as optimal points of operation with resulting infidelities of $1-F \approx 10^{-2}-10^{-3}$.

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Guillermo F. Peñas, Ricardo Puebla, Tomás Ramos, Peter Rabl, Juan José García-Ripoll. 2021-10-05. Universal deterministic quantum operations in microwave quantum links. https://doi.org/10.1103/physrevapplied.17.054038

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