A Phase Frequency Detector (PFD) for spectral puritytransfer with offset frequencies up to 10 GHz

The realization of ultra-stable lasers is both a technically challenging and
costly endeavour. Implementing more than one laser with such stability and
phase coherence is a prerequisite for a large number of experiments, like
optical clocks, two photon spectroscopy, and Raman transitions.
We present a phase frequency detector module (PFD) allowing spectral
purity transfer from an Ultra-stable laser stabilized to a very high finesse
cavity to both a Difference Frequency Comb (DFC) and directly to a second
CW laser with offset frequencies in the range of 5 MHz to 10 GHz.