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arXiv · 1003.3194

Planck Spectroscopy and the Quantum Noise of Microwave Beam Splitters

M. Mariantoni·E. P. Menzel·F. Deppe·M. A. Araque Caballero·A. Baust·T. Niemczyk·E. Hoffmann·E. Solano·A. Marx·R. Gross
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Abstract

We use a correlation function analysis of the field quadratures to characterize both the black body radiation emitted by a 50 Ohm load resistor and the quantum properties of two types of beam splitters in the microwave regime. To this end, we first study vacuum fluctuations as a function of frequency in a Planck spectroscopy experiment and then measure the covariance matrix of weak thermal states. Our results provide direct experimental evidence that vacuum fluctuations represent the fundamental minimum quantum noise added by a beam splitter to any given input signal.

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M. Mariantoni, E. P. Menzel, F. Deppe, M. A. Araque Caballero, A. Baust, T. Niemczyk, E. Hoffmann, E. Solano, A. Marx, R. Gross. 2010-03-16. Planck Spectroscopy and the Quantum Noise of Microwave Beam Splitters. https://doi.org/10.1103/physrevlett.105.133601

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