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arXiv · 1403.0031

Universal quantum gates on microwave photons assisted by circuit quantum electrodynamics

Ming Hua·Ming-Jie Tao·Fu-Guo Deng
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Abstract

Based on a microwave-photon quantum processor with two superconducting resonators coupled to one transmon qutrit, we construct the controlled-phase (c-phase) gate on microwave-photon-resonator qudits, by combination of the photon-number-dependent frequency-shift effect on the transmon qutrit by the first resonator and the resonant operation between the qutrit and the second resonator. This distinct feature provides us a useful way to achieve the c-phase gate on the two resonator qudits with a higher fidelity and a shorter operation time, compared with the previous proposals. The fidelity of our c-phase gate can reach 99.51% within 93 ns. Moreover, our device can be extended easily to construct the three-qudit gates on three resonator qudits, far different from the existing proposals. Our controlled-controlled-phase gate on three resonator qudits is accomplished with the assistance of a transmon qutrit and its fidelity can reach 92.92% within 124.64 ns.

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Ming Hua, Ming-Jie Tao, Fu-Guo Deng. 2014-08-01. Universal quantum gates on microwave photons assisted by circuit quantum electrodynamics. https://doi.org/10.1103/physreva.90.012328

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