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Quantum superposition of a single microwave photon in two different colour states



Eva A. Zakka-Bajjani, Francois E. Nguyen, Minhyea Lee, Leila R. Vale, Raymond Simmonds, Joe Aumentado


The ability to manipulate photonic states is an important tool for quantum information processing. In cavity quantum electrodynamics (QED), coupling between bosonic modes has, until now, required a qubit to mediate the interaction. As an alternative, it is also possible to generate this coupling using parametric frequency conversion. In this work, we accomplish this in a superconducting microwave circuit by parametrically coupling resonator harmonics, realizing a generalized beam- splitter interaction between cavity modes. We demonstrate this by coherently manipulating a single photon Fock state in a strongly-coupled mode basis. This introduces a new tool for circuit-based QED, creating a linear optical element that had previously been confined to propagating waves and extends the possibilities for the developing field of quantum microwave photonics.


Zakka-Bajjani, E. , Nguyen, F. , Lee, M. , Vale, L. , Simmonds, R. and Aumentado, J. (2011), Quantum superposition of a single microwave photon in two different colour states, Science/AAAS, [online], (Accessed May 22, 2024)


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Created July 2, 2011, Updated October 12, 2021