Atomic gyroscopes are a new, recently envisioned, type of atomic MEMS. Nuclear-spin based gyroscopes were identified in a comparative analysis of compact gyroscopes as a class of promising rotation sensors that can rival state-of-the-art gyroscopes. Use of nuclear spins for the detection of inertial rotation accounts for their intrinsic high precision.
Atomic gyroscopes measure angle or angular rate by observing response of the hyperpolarized nuclei to an inertial rotation. Certain noble gas nuclei possess an inherent magnetic moment. These nuclei can be spin-polarized by optically pumping an alkali vapor, which transfers its polarization to the nuclei through a process know as spin exchange. When subjected to a static magnetic field, the spin-polarized nuclei will precess about the magnetic field lines at the Larmor precession frequency. If the Larmor precession is observed in a coordinate frame that rotates at an angular rate with respect to an inertial frame of reference, the observed frequency will be the difference between the Larmor precession and inertial input rates. This frequency can be detected as a modulation of the light intensity of a circularly polarized beam that is transmitted through the sample. The light is collected on a photodetector and the angular rate proportional to the frequency shift is extracted from the signal.
This type of devices has an opportunity to revolutionize the entire market of high-precision sensors, and enable the world-first chip-scale gyroscope with the navigation-grade performance.