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Updated: Jun 12, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Self-excitation and feedback cooling of an isolated proton
N Guise1, J DiSciacca, G Gabrielse
1Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Abstract:
The first one-proton self-excited oscillator (SEO) and one-proton feedback cooling are demonstrated. In a Penning trap with a large magnetic gradient, the SEO frequency is resolved to the high precision needed to detect a one-proton spin flip. This is after undamped magnetron motion is sideband cooled to a 14 mK theoretical limit, and despite random frequency shifts (typically larger than those from a spin flip) that take place every time sideband cooling is applied. The observations open a possible path towards a million-fold improved comparison of the p and p magnetic moments.
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