Progress on novel atomic magnetometer and gyroscope based on self-sustaining of electron spins

Abstract

The gyroscope based on atomic technology has the potential to provide the end user a high-performance device in a small package with low-power. Generally, the atomic gyroscope detects the rotation or angular rate of the object by measuring the Larmor precession frequency of spins. However, the precision is limited by the shorter coherence time caused by relaxation effects, and since the nuclear spin precession is often used in detection for atomic gyroscope, longer polarization time limits its application environment. Presented in this paper is a self-sustaining gyroscope based on electron spins. By non-destructively measuring the phase of the Larmor precession and regenerating the coherence via optical pumping, the Larmor precession can persist indefinitely, and the system can quickly regain polarization to environmental variations. Magnetic field measurement has been accomplished by using the self-sustaining technology. The precision of the magnetometer increases with time following a much faster τ-1 rule rather than the traditional τ-1/2 rule. The mean sensitivity is close to the shot noise in 300 ms, and the magnetometer has a quick response to sudden magnetic change. The self-sustaining technology can hopefully improve the measurement precision and the response time of the atomic gyroscope.