Atomic magnetometer with microfabricated vapor cells based on coherent population trapping

An atomic magnetometer based on coherent population trapping (CPT) resonances in microfabricated vapor cells is demonstrated. Fabricated by the micro-electro-mechanical-system (MEMS) technology, the cells are filled with Rb and Ne at a controlled pressure. An experimental apparatus is built for characterizing properties of microfabricated vapor cells via the CPT effects. The typical CPT linewidth is measured to be about 3 kHz (1.46 kHz with approximately zero laser intensity) for the rubidium D1 line at about 90 ^°C. The effects of pressure, temperature and laser intensity on CPT linewidth are studied experimentally. A closed-loop atomic magnetometer is finally finished with a sensitivity of 210.5 pT/Hz^1/2 at 1 Hz bandwidth. This work paves the way for developing an integrated chip-scale atomic magnetometer in the future.