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arXiv · 1901.10445

A Quantum Spectrometer for Arbitrary Noise

Daniel Goldwater·Peter Barker·Angelo Bassi·Sandro Donadi
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Abstract

We present a technique for recovering the spectrum of a non-Markovian bosonic bath and/or non-Markovian noises coupled to an harmonic oscillator. The treatment is valid under the conditions that the environment is large and hot compared to the oscillator, and that its temporal auto-correlation functions are symmetric with respect to time translation and reflection -- criteria which we consider fairly minimal. We model a demonstration of the technique as deployed in the experimental scenario of a nanosphere levitated in a Paul trap, and show that it would effectively probe the spectrum of an electric field noise source from $10^2\,-\,10^6$ Hz with a resolution inversely proportional to the measurement time. This technique may be deployed in quantum sensing, metrology, computing, and in experimental probes of foundational questions

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Daniel Goldwater, Peter Barker, Angelo Bassi, Sandro Donadi. 2019-01-29. A Quantum Spectrometer for Arbitrary Noise. https://doi.org/10.1103/physrevlett.123.230801

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