A widely tuneable and narrow linewidth diode laser for coherent spectroscopy

We report on the development of a diode laser system which is optimized for precision spectroscopy. It is based on a combination of diode lasers with optical feedback from a grating and diode lasers with optical feedback from a resonant cavity. So far we have achieved overall tuneabilities on the order of 50 nm, continuous tuneabilities in excess of 40 GHz, and short term linewidth below 66 kHz measured over 2.9 s in a 15 MHz scan. In comparison to grating stabilized diode lasers these lasers should feature reduced frequency noise at high Fourier-frequencies which should significantly ease phase-locking to a frequency comb. These lasers will be used for precision spectroscopy and coherent manipulation of ultra-cold HD⁺molecules.