Ultrastable lasers - new developments and applications

摘要

Optical clocks largely rely on interrogation lasers with sub-Hz linewidth and low short term instability. The laser stability is mostly determined by the properties of the cavities that are used as short term references. With suitable mounting the influence of vibrations is strongly suppressed and the short term stability is limited by thermal fluctuations to a fractional instability around 1·10~(-15). Here we give an overview of the present status of our ultrastable lasers used for optical clocks and present possible ways to further reduce their noise levels and to transfer their stability to other wavelengths and to remote lasers.