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arXiv · 2010.04375

Quantum oscillator noise spectroscopy via displaced cat states

Alistair R. Milne·Cornelius Hempel·Li Li·Claire L. Edmunds·Harry J. Slatyer·Harrison Ball·Michael R. Hush·Michael J. Biercuk
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Abstract

Quantum harmonic oscillators are central to many modern quantum technologies. We introduce a method to determine the frequency noise spectrum of oscillator modes through coupling them to a qubit with continuously driven qubit-state-dependent displacements. We reconstruct the noise spectrum using a series of different drive phase and amplitude modulation patterns in conjunction with a data-fusion routine based on convex optimization. We apply the technique to the identification of intrinsic noise in the motional frequency of a single trapped ion with sensitivity to fluctuations at the sub-Hz level in a spectral range from quasi-DC up to 50 kHz.

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Alistair R. Milne, Cornelius Hempel, Li Li, Claire L. Edmunds, Harry J. Slatyer, Harrison Ball, Michael R. Hush, Michael J. Biercuk. 2020-10-09. Quantum oscillator noise spectroscopy via displaced cat states. https://doi.org/10.1103/physrevlett.126.250506

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