HYBRID OPTICAL AND ELECTRONIC LASER LOCKING USING SLOW LIGHT DUE TO SPECTRAL HOLES

We report on a narrow linewidth laser diode system that is stabilized using both optical and electronic feedback to a spectral hole in cryogenic Tm:YAG. The large group delay of the spectral hole leads to a laser with very low phase noise. The laser has proved useful for quantum optics and sensing applications involving cryogenic rare-earth-ion dopants.