Laser frequency stabilization using regenerative spectral hole burning

We demonstrate laser frequency stabilization using a continuously regenerated transient spectral hole in an inhomogeneously broadened resonance of a solid. Regenerative transient holes provide extreme stabilization for time scales appropriate for spectroscopy, signal processing, ranging, and interferometry. Stabilization to 20 Hz on a 10-ms time scale using spectral holes at 793 nm in ${\mathrm{Tm}}^{3+}{:\mathrm{Y}}_3{\mathrm{Al}}_5{\mathrm{O}}_{12}$ gives substantial improvement in the reliability of stimulated photon echoes in the same material and enables the observation of a third population storage mechanism for hole burning in ${\mathrm{Tm}}^{3+}{:\mathrm{Y}}_3{\mathrm{Al}}_5{\mathrm{O}}_{12}.$