A simple digital system for tuning and long-term frequency stabilisation of a CW Ti:Sapphire laser

摘要

We have implemented a simple and cost-effective digital system for long-termfrequency stabilisation and locking to an arbitrary wavelength of thesingle-frequency ring CW Ti:Sapphire laser. This system is built around twoconfocal Fabry-Perot cavities, one of which is used to narrow short-term linewidth of the laser and the other to improve long-term stability of the laserfrequency. The second interferometer is also in the path of the radiation froman external-cavity diode laser stabilized to an atomic transition. Our systemis an extension of a commercial Tekhnoscan laser lock. This system has beensuccessfully used in experiments on high-resolution laser spectroscopy ofultracold Rydberg atoms.