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arXiv · 1404.3242

Observation and interpretation of motional sideband asymmetry in a quantum electro-mechanical device

A. J. Weinstein·C. U. Lei·E. E. Wollman·J. Suh·A. Metelmann·A. A. Clerk·K. C. Schwab
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Abstract

Quantum electro-mechanical systems offer a unique opportunity to probe quantum noise properties in macroscopic devices, properties which ultimately stem from the Heisenberg Uncertainty Principle. A simple example of this is expected to occur in a microwave parametric transducer, where mechanical motion generates motional sidebands corresponding to the up and down frequency-conversion of microwave photons. Due to quantum vacuum noise, the rates of these processes are expected to be unequal. We measure this fundamental imbalance in a microwave transducer coupled to a radio-frequency mechanical mode, cooled near the ground state of motion. We also discuss the subtle origin of this imbalance: depending on the measurement scheme, the imbalance is most naturally attributed to the quantum fluctuations of either the mechanical mode or of the electromagnetic field.

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A. J. Weinstein, C. U. Lei, E. E. Wollman, J. Suh, A. Metelmann, A. A. Clerk, K. C. Schwab. 2014-04-11. Observation and interpretation of motional sideband asymmetry in a quantum electro-mechanical device. https://doi.org/10.1103/physrevx.4.041003

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