| Autor: |
Jasperse, M., Kewming, M. J., Fischer, S. N., Pakkiam, P., Anderson, R. P., Turner, L. D. |
| Rok vydání: |
2017 |
| Předmět: |
|
| Zdroj: |
Phys. Rev. A 96, 063402 (2017) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevA.96.063402 |
| Popis: |
We describe a dispersive Faraday optical probe of atomic spin which performs a weak measurement of spin projection of a quantum gas continuously for more than one second. To date focusing bright far-off-resonance probes onto quantum gases has proved invasive, due to strong scalar and vector light shifts exerting dipole and Stern-Gerlach forces. We show that tuning the probe near the magic-zero wavelength at 790 nm between the fine-structure doublet of $^{87}$Rb cancels the scalar light shift, and careful control of polarization eliminates the vector light shift. Faraday rotations due to each fine-structure line reinforce at this wavelength, enhancing the signal-to-noise ratio for a fixed rate of probe-induced decoherence. Using this minimally-invasive spin probe we perform microscale atomic magnetometry at high temporal resolution. Spectrogram analysis of the Larmor precession signal of a single spinor Bose-Einstein condensate measures a time-varying magnetic field strength with 1 {\mu}G accuracy every 5 ms; or equivalently makes > 200 successive measurements each at $10\,\mathrm{pT/\sqrt{Hz}}$ sensitivity. |
| Databáze: |
arXiv |
| Externí odkaz: |
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