Rotating polarization magnetometry

Abstract

Precise magnetometry is vital in numerous scientific and technological applications. At the forefront of sensitivity, optical atomic magnetometry, particularly techniques utilizing nonlinear magneto-optical rotation (NMOR), enables ultraprecise measurements across a broad field range. Despite their potential, these techniques reportedly lose sensitivity at higher magnetic fields, which is attributed to the alignment-to-orientation conversion (AOC) process. In our study, we utilize light with continuously rotating linear polarization to avoid AOC, producing robust optical signals and achieving high magnetometric sensitivity over a dynamic range nearly three times greater than Earth's magnetic field. We demonstrate that employing rotating polarization surpasses other NMOR techniques that use modulated light. Our findings also indicate that the previously observed signal deterioration is not due to AOC, suggesting an alternative cause for this decline.