Frequency locking of tunable diode lasers to a stabilized ring-cavity resonator

摘要

We demonstrate a technique for locking the frequency of a tunable diode laserto a ring-cavity resonator. The resonator is stabilized to a diode laser whichis in turn locked to an atomic transition, thus giving it absolute frequencycalibration. The ring-cavity design has the principal advantage that there isno feedback destabilization of the laser. The cavity has a free-spectral rangeof 1.3 GHz and $Q$ of about 35, which gives robust locking of the laser. Thelocked laser is able to track large scans of the cavity.