Discrete-time quadrature feedback cooling of a radio-frequency mechanical resonator

M. Poot; S. Etaki; H. Yamaguchi; H. S. J. van der Zant

doi:10.1063/1.3608148

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arXiv · 1106.2106

Discrete-time quadrature feedback cooling of a radio-frequency mechanical resonator

M. Poot·S. Etaki·H. Yamaguchi·H. S. J. van der Zant

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Abstract

We have employed a feedback cooling scheme, which combines high-frequency mixing with digital signal processing. The frequency and damping rate of a 2 MHz micromechanical resonator embedded in a dc SQUID are adjusted with the feedback, and active cooling to a temperature of 14.3 mK is demonstrated. This technique can be applied to GHz resonators and allows for flexible control strategies.

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M. Poot, S. Etaki, H. Yamaguchi, H. S. J. van der Zant. 2011-06-10. Discrete-time quadrature feedback cooling of a radio-frequency mechanical resonator. https://doi.org/10.1063/1.3608148

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