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arXiv · 2302.07442

Microwave amplification via interfering multi-photon processes in a half-waveguide quantum electrodynamics system

Fahad Aziz·Kuan Ting Lin·Ping Yi Wen·Samina·Yu Chen Lin·Emely Wiegand·Ching-Ping Lee·Yu-Ting Cheng·Ching-Yeh Chen·Chin-Hsun Chien·Kai-Min Hsieh·Yu-Huan Huang·Ian Hou·Jeng-Chung Chen·Yen-Hsiang Lin·Anton Frisk Kockum·Guin Dar Lin·Io-Chun Hoi
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Abstract

We investigate the amplification of a microwave probe signal by a superconducting artificial atom, a transmon, strongly coupled to the end of a one-dimensional semi-infinite transmission line. The end of the transmission line acts as a mirror for microwave fields. Due to the weak anharmonicity of the artificial atom, a strong pump field creates multi-photon excitations among the dressed states. Transitions between these dressed states, Rabi sidebands, give rise to either amplification or attenuation of the weak probe. We obtain a maximum amplitude amplification of about 18 %, higher than in any previous experiment with a single artificial atom, due to constructive interference between Rabi sidebands. We also characterize the noise properties of the system by measuring the spectrum of spontaneous emission.

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Fahad Aziz, Kuan Ting Lin, Ping Yi Wen, Samina, Yu Chen Lin, Emely Wiegand, Ching-Ping Lee, Yu-Ting Cheng, Ching-Yeh Chen, Chin-Hsun Chien, Kai-Min Hsieh, Yu-Huan Huang, Ian Hou, Jeng-Chung Chen, Yen-Hsiang Lin, Anton Frisk Kockum, Guin Dar Lin, Io-Chun Hoi. 2023-02-15. Microwave amplification via interfering multi-photon processes in a half-waveguide quantum electrodynamics system. https://doi.org/10.1038/s41534-025-00993-3

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