Patent ID: 9541398
Date: 2017-01-10
CPC Classifications: G01C,G01R

Claim:
1. An apparatus for sensing rotations, the apparatus comprising: a magnet that generates a first magnetic field; a cell containing at least a vaporized source of alkali atoms and atoms of one or more active nuclear magnetic resonance (NMR) isotopes; a light source configured to emit a diverging light that passes through the cell; a polarizing beam splitter opposite the light source and configured to split the diverging light that has passed through the cell into orthogonally polarized components; and a plurality of photodetectors, each of the photodetectors being configured to detect one of the orthogonally polarized components of the light that has passed through the cell and been split by the polarizing beam splitter and to generate a respective signal indicative of intensity of detected light for use in differential detection, wherein a longitudinal component of the diverging light acts as a pump beam for optically pumping the alkali atoms in the cell and, in conjunction with at least a second magnetic field orthogonal to the first magnetic field or a modulation of the diverging light, causing the alkali atoms and the one or more active NMR isotope atoms to precess about the first magnetic field, and wherein a transverse component of the diverging light acts as a probe beam for observing the precession about the first magnetic field.