A microfabricated photonic magnetometer

An integrated optically-controlled sensor, suitable for remote, high-sensitivity detection of magnetic fields is presented. The operation of the sensor both in earth field in a Bell-Bloom type configuration is demonstrated as well as in a spin-exchange relaxation-free mode (SERF) and reach sensitivities better than 500 fT/radicHz at 10 Hz. The design and initial measurements of a small atomic magnetometer that has no electrical connections near the sensor head is presented. The sensor is fabricated by use of methods derived from microelectromechanical (MEMS) systems and integrated with off-the-shelf micro-optical components. Light is coupled through fibers to and from the sensor head for interrogation of the atoms. Heating of the atomic vapor is achieved by a second fiber-coupled laser source, utilizing the absorption properties of the vapor cell.