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arXiv · 2410.16413

Measuring spin-noise correlation function via time reversal

M. V. Dubinin·A. A. Fomin·G. G. Kozlov·M. Yu. Petrov·V. S. Zapasskii
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Abstract

We propose a simple method of measuring the autocorrelation function of a spin noise based on multiplication and averaging two digitized signal traces, with one of them being a time-reversed copy of the other. This procedure allows one to obtain, with lower computational expenses, all the information usually derived in the Fourier transform spin-noise spectroscopy, retaining all the merits of the latter. We successfully applied this method to the measurements of spin noise in cesium vapors by using a digital oscilloscope in the capacity of the analog-to-digital converter. Specific opportunities of this experimental approach as applied to a more general problem of studying the nature of light-intensity noise are discussed.

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M. V. Dubinin, A. A. Fomin, G. G. Kozlov, M. Yu. Petrov, V. S. Zapasskii. 2024-10-21. Measuring spin-noise correlation function via time reversal. https://arxiv.org/abs/2410.16413

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