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arXiv · 2506.18872

Ultra-low damping of the translational motion of a composite graphite rod in a magneto-gravitational trap

Connor E. Murphy·Cody Jessup·Tahereh Naderishahab·Yateendra Sihag·Max M. Fields·Leonardo R. Werneck·Zachariah B. Etienne·Brian D'Urso
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Abstract

We demonstrate an ultra-low dissipation, one-dimensional mechanical oscillator formed by levitating a millimeter-scale composite graphite rod in a room-temperature magneto-gravitational trap. The trap's magnetic field geometry, based on a linear quadrupole, eliminates first-order field gradients in the axial direction, yielding a low oscillation frequency with ultra-low eddy-current losses. Direct ring-down measurements under vacuum compare the damping of the vertical and axial motion; while the vertical motion damps in seconds, the axial motion damps with a time constant of over 5 days. Analysis reveals that this dramatic difference in damping is a result of the symmetry of the magnetic field and the anisotropy of the trap strength. The results are remarkably robust, demonstrating a potential platform for inertial and gravitational sensing.

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Connor E. Murphy, Cody Jessup, Tahereh Naderishahab, Yateendra Sihag, Max M. Fields, Leonardo R. Werneck, Zachariah B. Etienne, Brian D'Urso. 2025-06-23. Ultra-low damping of the translational motion of a composite graphite rod in a magneto-gravitational trap. https://doi.org/10.1063/5.0287198

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