A table-top high-sensitivity gyroscope based on slow light and cavity enhanced photon drag

A high-sensitivity gyroscope is vital for both investigation of the fundamental physics and monitor of the subtle variation of Earth's behaviors. However, it is challenge to realize a portable gyroscope with sensitivity approaching a small fraction of the Earth's rotation rate. Here, we theoretically propose a method for implementing a table-top gyroscope with remarkably high sensitivity based on photon drag in a rotating dielectric object. By inserting an $\text{Er}^{3+}$-doped glass rod in a Fabry-P\'{e}rot optical cavity with only 20 cm length, we theoretically show that the giant group refractive index and the narrowing cavity linewidth due to slow light can essentially increase the nonreciprocal phase shift due to the photon drag to achieve a rotation sensitivity of $26$ frad/s/$\sqrt{Hz}$. This work paves the way to accurately detect tiny variations of the Earth's rotation rate and orientation, and even can test the geodetic and frame-dragging effects predicted by the general relativity with a small-volume equipment.