Precision spectroscopy using a partially stabilized frequency comb.

ABSTRACT

We present a simple method for precision spectroscopy using an optical frequency comb. One mode of a 1 GHz repetition rate mode-locked Tisapphire laser is offset-locked to an Rb-stabilized diode laser. This partially stabilized frequency comb stays locked, unattended, for hours at a time. Using the measured offset frequency and repetition rate, we calculate the frequency of each comb mode with absolute uncertainty of about 10 kHz in a 10 s measurement window. We demonstrate the capabilities and limitations of this approach with measurements in Rb, Cs, and Ca.