Compact, Ti:sapphire based methane-stabilized optical molecular frequency comb and clock

Abstract

A compact optical clock and frequency comb system is presented, based on a 1 GHz octave spanning Ti:sapphire laser referenced to the F2[superscript(2)](P(7),v[subscript 3]) optical transition in methane at 3.39 μm. The reference methane transition is accessed by a stabilized HeNe laser in a compact transportable format. The output from the octave spanning Ti:sapphire laser is used to generate a mid-IR comb at the reference wavelength 3.39 μm. Direct comparison of the stabilized optical frequency comb with a ULE cavity stabilized diode laser at 674 nm shows an Allan Deviation of the frequency comb of 3x10[superscript -14] in 20 s.