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arXiv · 2510.08732

Spin-Locking Spectroscopy of Harmonic Motion

Florian Kranzl·Adria Rospars·Johannes Franke·Manoj K. Joshi·Rainer Blatt·Christian F. Roos
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Abstract

Characterization of noise of a quantum harmonic oscillator is important for many experimental platforms. We experimentally demonstrate motional spin-locking spectroscopy, a method that allows us to directly measure the motional noise spectrum of a quantum harmonic oscillator. We measure motional noise of a single trapped ion in a frequency range from 200 Hz to 5 kHz with a power spectral density that resolves noise over two orders of magnitude. Coherent modulations in the oscillation frequency of the oscillator can be probed with a relative frequency sensitivity at the $10^{-6}$ level.

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Florian Kranzl, Adria Rospars, Johannes Franke, Manoj K. Joshi, Rainer Blatt, Christian F. Roos. 2025-10-09. Spin-Locking Spectroscopy of Harmonic Motion. https://arxiv.org/abs/2510.08732

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