Long term frequency stabilization and frequency drift suppression of the 313 nm laser

Abstract

A 313 nm ultraviolet (UV) laser is stabilized through the Pound–Drever–Hall method, and its frequency drift is suppressed by a remote frequency drift correction system. The 313 nm laser is generated through an external cavity diode laser at 1252 nm and two cascaded second harmonic generation (SHG) stages. By locking the 626 nm from the first SHG stage to an ULE cavity and evaluating the beat signal between the 626 nm laser and an optical frequency comb, the 313 nm laser frequency instabilities of 1.80 ×10−12 at 1 s and 4.70 ×10−14 at 64 s averaging time are obtained. With the remote frequency drift correction system, the frequency drift of 313 nm laser is reduced to 0.02 (6) kHz/h. Individual ions in a beryllium Coulomb crystal cooled by the stable 313 nm laser are identified within the 240 s.