A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulator<xref ref-type="fn" rid="cpb142444fn1">*</xref>

A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulator*

Zhang Yan-Yan^a), Yan Lu-Lu^a), Zhao Wen-Yu^a),^b), Meng Sen^a),^c), Fan Song-Tao^a),^b), Zhang Long^a), Guo Wen-Ge^c), Zhang Shou-Gang^a), Jiang Hai-Feng^a)†

Schematic diagram of the Er:fiber femtosecond laser frequency comb. The thick solid lines represent free-space paths, the thin solid lines represent fiber paths, and the dotted lines represent electrical paths. λ /2: half-wave plate; λ /4: quarter-wave plate; WDM: wavelength division multiplexer; ISO: isolator; PBS: polarization beam splitter; CO: collimator; PD: photodetector; BPF: bandpass filter; PPLN: periodically poled lithium niobate; HNLF: highly nonlinear fiber; LF: loop filter; HVA: high voltage amplifier; SYN: synthesizer.