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arXiv · 2310.03880

Linear cooling of a levitated micromagnetic cylinder by vibration

Chris Timberlake·Elliot Simcox·Hendrik Ulbricht
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Abstract

We report feedback cooling of translational and librational degrees of freedom of a levitated micromagnet cylinder, utilizing a piezoelectric actuator to apply linear feedback to high-Q mechanical modes. The normal modes are measured with a superconducting pick-up coil coupled to a DC SQUID, and phase information is fed back to the piezoelectric actuator to feedback cool a center-of-mass mode to $\sim$7 K, and a librational mode to $830 \pm 200$ mK. Q-factors of $1.0 \times 10^7$ are evaluated for the center-of-mass mode. We find that it is plausible to achieve ground state cooling of the center-of-mass mode by introducing vibration isolation, optimizing the geometry of the pick-up coil to focus on the specific mode of interest and utilizing a state-of-the-art SQUID for detection.

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Chris Timberlake, Elliot Simcox, Hendrik Ulbricht. 2023-10-05. Linear cooling of a levitated micromagnetic cylinder by vibration. https://doi.org/10.1103/physrevresearch.6.033345

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