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arXiv · 1609.07353

Photon Statistics of Propagating Thermal Microwaves

J. Goetz·S. Pogorzalek·F. Deppe·K. G. Fedorov·P. Eder·M. Fischer·F. Wulschner·E. Xie·A. Marx·R. Gross
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Abstract

In experiments with superconducting quantum circuits, characterizing the photon statistics of propagating microwave fields is a fundamental task. We quantify the $n^{2}\,{+}\,n$ photon number variance of thermal microwave photons emitted from a black-body radiator for mean photon numbers $0.05\,{\lesssim}\,n\,{\lesssim}\,1.5$. We probe the fields using either correlation measurements or a transmon qubit coupled to a microwave resonator. Our experiments provide a precise quantitative characterization of weak microwave states and information on the noise emitted by a Josephson parametric amplifier.

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J. Goetz, S. Pogorzalek, F. Deppe, K. G. Fedorov, P. Eder, M. Fischer, F. Wulschner, E. Xie, A. Marx, R. Gross. 2016-09-23. Photon Statistics of Propagating Thermal Microwaves. https://doi.org/10.1103/physrevlett.118.103602

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