Phase-stable and selectable repetition-rate division of an optical frequency comb

We present a phase-stable and selectable repetition-rate (${f}_{\text{rep}}$) divider (PSRD) of an optical frequency comb (OFC) by down-picking a train of pulses from the fundamental OFC phase coherently. The PSRD operating at the integer pulse-picking order $p$ uses an acousto-optic modulator driven by a train of phase-synchronized single-cycle wave packets oscillating at the carrier frequency of ${f}_{c}\ensuremath{\equiv}{f}_{\text{rep}}$ and the gating frequency of ${f}_{g}^{p}\ensuremath{\equiv}{f}_{\text{rep}}/p$. The demonstrated PSRD can selectively pick a train of pulses with $p=2$ to 25 from the fundamental OFC with ${f}_{\text{rep}}=250$ MHz at 530 nm. Integrated phase noises from 10 Hz to 25 kHz offset frequency from the optical beat note between each down-picked OFC and the fundamental OFC are measured to be about ($59\ifmmode\pm\else\textpm\fi{}6$) mrad through the whole pulse picking order. The phase-coherent down-picked OFC could be of use for various applications where phase-stable and repetition-rate selectable OFCs are the essential radiation sources.