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arXiv · 1909.12295

Quantum Microwave Radiometry with a Superconducting Qubit

Zhixin Wang·Mingrui Xu·Xu Han·Wei Fu·Shruti Puri·S. M. Girvin·Hong X. Tang·S. Shankar·M. H. Devoret
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Abstract

The interaction of photons and coherent quantum systems can be employed to detect electromagnetic radiation with remarkable sensitivity. We introduce a quantum radiometer based on the photon-induced-dephasing process of a superconducting qubit for sensing microwave radiation at the sub-unit-photon level. Using this radiometer, we demonstrated the radiative cooling of a 1-K microwave resonator and measured its mode temperature with an uncertainty ~0.01 K. We have thus developed a precise tool for studying the thermodynamics of quantum microwave circuits, which provides new solutions for calibrating hybrid quantum systems and detecting candidate particles for dark matter.

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Zhixin Wang, Mingrui Xu, Xu Han, Wei Fu, Shruti Puri, S. M. Girvin, Hong X. Tang, S. Shankar, M. H. Devoret. 2019-09-26. Quantum Microwave Radiometry with a Superconducting Qubit. https://doi.org/10.1103/physrevlett.126.180501

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