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arXiv · 1508.05290

Quantum magnonics: magnon meets superconducting qubit

Yutaka Tabuchi·Seiichiro Ishino·Atsushi Noguchi·Toyofumi Ishikawa·Rekishu Yamazaki·Koji Usami·Yasunobu Nakamura
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Abstract

The techniques of microwave quantum optics are applied to collective spin excitations in a macroscopic sphere of ferromagnetic insulator. We demonstrate, in the single-magnon limit, strong coupling between a magnetostatic mode in the sphere and a microwave cavity mode. Moreover, we introduce a superconducting qubit in the cavity and couple the qubit with the magnon excitation via the virtual photon excitation. We observe the magnon-vacuum-induced Rabi splitting. The hybrid quantum system enables generation and characterization of non-classical quantum states of magnons.

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Yutaka Tabuchi, Seiichiro Ishino, Atsushi Noguchi, Toyofumi Ishikawa, Rekishu Yamazaki, Koji Usami, Yasunobu Nakamura. 2015-08-21. Quantum magnonics: magnon meets superconducting qubit. https://doi.org/10.1016/j.crhy.2016.07.009

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