Acceleration sensing with magnetically levitated oscillators above a superconductor
Abstract
We experimentally demonstrate the stable trapping of a permanent magnet sphere above a lead superconductor, at vacuum pressures of 4 × 10 - 8 mbar. The levitating magnet behaves as a harmonic oscillator, with frequencies in the 4-31 Hz range detected, and shows promise to be an ultrasensitive acceleration sensor. We directly apply an acceleration to the magnet with a current carrying wire, which we use to measure a background noise of ∼ 10 - 10 m / √{ Hz } at 30.75 Hz frequency. With current experimental parameters, we find an acceleration sensitivity of Sa 1 / 2 = 1.2 ± 0.2 × 10 - 10 g / √{ Hz } , for a thermal noise limited system. By considering a 300 mK environment, at a background helium pressure of 1 × 10 - 10 mbar, acceleration sensitivities of Sa 1 / 2 ∼ 3 × 10 - 15 g / √{ Hz } could be possible with ideal conditions and vibration isolation. To feasibly measure with such a sensitivity, feedback cooling must be implemented.
- Publication:
-
Applied Physics Letters
- Pub Date:
- November 2019
- DOI:
- 10.1063/1.5129145
- arXiv:
- arXiv:1910.07078
- Bibcode:
- 2019ApPhL.115v4101T
- Keywords:
-
- Physics - Applied Physics;
- Condensed Matter - Superconductivity;
- Physics - Optics;
- Quantum Physics
- E-Print:
- 5 pages, 3 figures, The following article has been accepted by Applied Physics Letters