Optimization of a Single Beam All-optical Magnetometer using a microfabricated ⁸⁷Rb Vapor Cell

We demonstrate a current-modulated single laser beam Bell-Bloom magnetometer measruing Earth-scale magnetic fields where a microfabricated gas cell with inner dimensions of 3 mm * 3 mm * 2 mm filled with a 87Rb vapor and nitrogen is applied. A current-modulated single laser beam drives the spin precession of 87Rb and the resulting spin precession induces the polarization rotation of the laser beam. By using balanced detection of the polarization-rotated laser beam, the spin precession can be observed. We investigate sensitivities of the magnetometer by varying detuning, averaged intensity, modulation depth, and polarization of the single laser beam in order to optimize the magnetometer.