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arXiv · 1507.04209

Squeezing of quantum noise of motion in a micromechanical resonator

J. -M. Pirkkalainen·E. Damskägg·M. Brandt·F. Massel·M. A. Sillanpää
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Abstract

A pair of conjugate observables, such as the quadrature amplitudes of harmonic motion, have fundamental fluctuations which are bound by the Heisenberg uncertainty relation. However, in a squeezed quantum state, fluctuations of a quantity can be reduced below the standard quantum limit, at the cost of increased fluctuations of the conjugate variable. Here we prepare a nearly macroscopic moving body, realized as a micromechanical resonator, in a squeezed quantum state. We obtain squeezing of one quadrature amplitude $1.1 \pm 0.4$ dB below the standard quantum limit, thus achieving a long-standing goal of obtaining motional squeezing in a macroscopic object.

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J. -M. Pirkkalainen, E. Damskägg, M. Brandt, F. Massel, M. A. Sillanpää. 2015-10-14. Squeezing of quantum noise of motion in a micromechanical resonator. https://doi.org/10.1103/physrevlett.115.243601

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