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arXiv · 1403.7796

Shot-noise-limited magnetometer with sub-pT sensitivity at room temperature

Vito Giovanni Lucivero·Pawel Anielski·Wojciech Gawlik·Morgan W. Mitchell
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Abstract

We report a photon shot-noise-limited (SNL) optical magnetometer based on amplitude modulated optical rotation using a room-temperature $^{85}$Rb vapor in a cell with anti-relaxation coating. The instrument achieves a room-temperature sensitivity of $70$ fT/$\sqrt{\mathrm{Hz}}$ at $7.6$ $μ$T. Experimental scaling of noise with optical power, in agreement with theoretical predictions, confirms the SNL behaviour from $5$ $μ$T to $75$ $μ$T. The combination of best-in-class sensitivity and SNL operation makes the system a promising candidate for application of squeezed light to a state-of-the-art atomic sensor.

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Vito Giovanni Lucivero, Pawel Anielski, Wojciech Gawlik, Morgan W. Mitchell. 2014-11-20. Shot-noise-limited magnetometer with sub-pT sensitivity at room temperature. https://doi.org/10.1063/1.4901588

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