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arXiv · 0805.3797

Faraday spectroscopy of atoms confined in a dark optical trap

Matthew L. Terraciano·Mark Bashkansky·Fredrik Fatemi
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Abstract

We demonstrate Faraday spectroscopy with high duty cycle and sampling rate using atoms confined to a blue-detuned optical trap. Our trap consists of a crossed pair of high-charge-number hollow laser beams, which forms a dark, box-like potential. We have used this to measure transient magnetic fields in a 500-micron-diameter spot over a 400 ms time window with nearly unit duty cycle at a 500 Hz sampling rate. We use these measurements to quantify and compensate time-varying magnetic fields to ~10 nT per time sample.

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Matthew L. Terraciano, Mark Bashkansky, Fredrik Fatemi. 2008-05-24. Faraday spectroscopy of atoms confined in a dark optical trap. https://doi.org/10.1103/physreva.77.063417

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