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arXiv · 1506.06363

Engineering entangled microwave photon states via multiphoton interactions between two cavity fields and a superconducting qubit

Yan-Jun Zhao·Chang-Qing Wang·Xiaobo Zhu·Yu-xi Liu
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Abstract

It has been shown that there are not only transverse but also longitudinal couplings between microwave fields and a superconducting qubit with broken inversion symmetry of the potential energy. Using multiphoton processes induced by longitudinal coupling fields and frequency matching conditions, we design a universal algorithm to produce arbitrary superpositions of two-mode photon states of microwave fields in two separated transmission line resonators, which are coupled to a superconducting qubit. Based on our algorithm, we analyze the generation of evenly-populated states and NOON states. Compared to other proposals with only single-photon process, we provide an efficient way to produce entangled microwave states when the interactions between superconducting qubits and microwave fields are in the ultrastrong regime.

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Yan-Jun Zhao, Chang-Qing Wang, Xiaobo Zhu, Yu-xi Liu. 2015-06-21. Engineering entangled microwave photon states via multiphoton interactions between two cavity fields and a superconducting qubit. https://doi.org/10.1038/srep23646

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