Physical Review Letters

Levitated Nano-accelerometer Sensitized by Quantum Quench

Mitsuyoshi Kamba, Sotatsu Otabe, Ken Funo, Takahiro Sagawa, K. Aikawa

Published Jun 15, 2026• 0 citations

Abstract

We realize a nanoscale accelerometer with a levitated nanoparticle near the ground state, exploiting its dynamical behavior triggered by the abrupt quench of its trapping potential. We find that rapid quenching provides a readout time at which the sensitivity is enhanced by 2 orders of magnitude with a favorable combination of a large acceleration-induced displacement and a reduced position uncertainty, enabling us to detect a weak acceleration obscured by the zero-point fluctuation in the initial potential. With rapid quenching, the observed sensitivity is in good agreement with a numerical simulation based on the quantum Langevin equation. Our results provide a step toward inertial sensing with levitated nanoparticles through time-optimal quench dynamics in the quantum regime.

DOI: 10.1103/js43-kq48

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