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arXiv · 1509.05653

Squeezed-light spin noise spectroscopy

Vito Giovanni Lucivero·Ricardo Jiménez-Martínez·Jia Kong·Morgan W. Mitchell
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Abstract

We report quantum enhancement of Faraday rotation spin noise spectroscopy by polarization squeezing of the probe beam. Using natural abundance Rb in 100 Torr of N_2 buffer gas, and squeezed light from a sub-threshold optical parametric oscillator stabilized 20 GHz to the blue of the D_1 resonance, we observe that an input squeezing of 3.0 dB improves the signal-to-noise ratio by 1.5 dB to 2.6 dB over the combined (power)$\otimes$(number density) ranges (0.5 mW to 4.0 mW )$\otimes$(1.5 x 10^{12} cm^{-3} to 1.3 x 10^{13} cm^{-3}), covering the ranges used in optimized spin noise spectroscopy experiments. We also show that squeezing improves the trade-off between statistical sensitivity and broadening effects, a previously unobserved quantum advantage.

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Vito Giovanni Lucivero, Ricardo Jiménez-Martínez, Jia Kong, Morgan W. Mitchell. 2015-09-18. Squeezed-light spin noise spectroscopy. https://doi.org/10.1103/physreva.93.053802

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