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arXiv · 2302.06930

All-microwave manipulation of superconducting qubits with a fixed-frequency transmon coupler

Shotaro Shirai·Yuta Okubo·Kohei Matsuura·Alto Osada·Yasunobu Nakamura·Atsushi Noguchi
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Abstract

All-microwave control of fixed-frequency superconducting quantum computing circuits is advantageous for minimizing the noise channels and wiring costs. Here we introduce a swap interaction between two data transmons assisted by the third-order nonlinearity of a coupler transmon under a microwave drive. We model the interaction analytically and numerically and use it to implement an all-microwave controlled-Z gate. The gate based on the coupler-assisted swap transition maintains high drive efficiency and small residual interaction over a wide range of detuning between the data transmons.

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Shotaro Shirai, Yuta Okubo, Kohei Matsuura, Alto Osada, Yasunobu Nakamura, Atsushi Noguchi. 2023-02-14. All-microwave manipulation of superconducting qubits with a fixed-frequency transmon coupler. https://doi.org/10.1103/physrevlett.130.260601

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