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arXiv · 2405.10886

Three-mode tunable coupler for superconducting two-qubit gates

Elena Yu. Egorova·Alena S. Kazmina·Ilya A. Simakov·Ilya N. Moskalenko·Nikolay N. Abramov·Daria A. Kalacheva·Viktor B. Lubsanov·Alexey N. Bolgar·Nataliya Maleeva·Ilya S. Besedin
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Abstract

Building a scalable universal high-performance quantum processor is a formidable challenge. In particular, the problem of realizing fast high-perfomance two-qubit gates of high-fidelity remains needful. Here we propose a building block for a scalable quantum processor consisting of two transmons and a tunable three-mode coupler allowing for a ZZ interaction control. We experimentally demonstrate the native CZ gate with the pulse duration of 60 ns achieving the two-qubit gate fidelity above 98%, limited mostly by qubit coherence time. Numerical simulations show that by optimizing the gate duration the fidelity can be pushed over 99.97%.

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Elena Yu. Egorova, Alena S. Kazmina, Ilya A. Simakov, Ilya N. Moskalenko, Nikolay N. Abramov, Daria A. Kalacheva, Viktor B. Lubsanov, Alexey N. Bolgar, Nataliya Maleeva, Ilya S. Besedin. 2024-05-17. Three-mode tunable coupler for superconducting two-qubit gates. https://arxiv.org/abs/2405.10886

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