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arXiv · 1712.07921

Real-Time Kalman Filter: Cooling of an Optically Levitated Nanoparticle

Ashley Setter·Marko Toroš·Jason F. Ralph·Hendrik Ulbricht
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Abstract

We demonstrate that a Kalman filter applied to estimate the position of an optically levitated nanoparticle, and operated in real-time within a Field Programmable Gate Array (FPGA), is sufficient to perform closed-loop parametric feedback cooling of the centre of mass motion to sub-Kelvin temperatures. The translational centre of mass motion along the optical axis of the trapped nanoparticle has been cooled by three orders of magnitude, from a temperature of 300K to a temperature of 162 +/- 15mK.

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Ashley Setter, Marko Toroš, Jason F. Ralph, Hendrik Ulbricht. 2017-12-21. Real-Time Kalman Filter: Cooling of an Optically Levitated Nanoparticle. https://doi.org/10.1103/physreva.97.033822

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