Sensitive spatially resolved magnetometry using a Bose-condensed gas with a bright probe

We demonstrate a sensitive spatially resolved magnetometer using a spinor Bose-Einstein condensate (BEC) of Rb-87 atoms with increased probe fluence. By performing a probe parameter search using a two-polarization phase contrast imaging technique, we find that the probe-induced atom loss, a major constraint in optical magnetometry with high-density gas, can be reduced. We attain a sensitivity of 5.4(6) mrad for the phase measurement of Larmor precession using a measurement area of 1.4 x 10(2) mu m(2) with a probe fluence of 4.1 x 10(5) mu m(-2). A dc magnetic field sensitivity of 5.0(4) pT/root Hz is attained with a probe fluence of 3.9 x 105 mu m(-2). The results should contribute to further enhancement of the sensitivity of a BEC magnetometer.

Automated summary

A sensitive spatially resolved magnetometer using a spinor Bose-Einstein condensate of Rb-87 atoms was demonstrated, showing reduced probe-induced atom loss with increased probe fluence. The sensitivity of the magnetometer was enhanced by optimizing the probe parameters, achieving high precision in measuring Larmor precession phase and dc magnetic field sensitivity. These results are expected to contribute to further enhancing the sensitivity of BEC magnetometers.