Fig. 2: Optical difference frequency division system.
From: Magic cancellation point for vibration resilient ultrastable microwave signal synthesis
a ODFD system diagram comprising two orthogonally polarized SBS lasers combined with an electro-optically modulated frequency comb. DRO dielectric resonator oscillator, PS phase shifter, LO local oscillator, IM intensity modulator, PM phase modulator, SOA semiconductor optical amplifier, PBS polarization beam splitter, PC polarization controller, OSA optical spectrum analyzer. The DRO is stabilized to the optical beat notes to perform division down to 10 GHz. b Flow diagram depicting the signal path from SBS pump lasers, EOM seed laser, and 10 GHz DRO driver to the stabilized frequency divider output. c EOM comb spectrum comprising successive stages of modulation. The comb span broadens with each stage of modulation up to a width of 11.5 nm for 1 intensity modulator and 5 phase modulator stages. d SBS laser spectrum with wavelength scale aligned to the plotted frequency comb spectrum. The two SBS lasers are orthogonally polarized and directly overlap with the comb lines.
