Experiments demonstrate technique for improved optical gyroscopes

AC10917 - Accurate navigation in an aircraft or other vehicle requires sensitive measurements of rotation of the vehicle. For example, ring laser gyroscopes are commonplace in navigation systems used today. Experiments reported in PRA, [link], demonstrate that the sensitivity of such devices may be increased substantially. These gyroscopes use an optical cavity, a series of mirrors in which laser light bounces in a closed path, which  effectively changes length when the gyroscope undergoes rotation. The frequency of light which may be sustained in the optical cavity changes correspondingly, and a measurement of the change in frequency gives the rotation rate of the cavity. By adding a rubidium vapor cell inside the optical cavity, the new results demonstrate that the frequency change of the cavity can be enhanced by a factor of as much as 15, the largest increase achieved in an experiment to date. The "dispersion-enhanced cavity" can be used for measuring rotation rates with substantially greater sensitivity, leading to more accurate measurements of rotation, and thereby, improving the accuracy of navigation systems.