[1] Du J T, Chang B, Li Z Y et al. Mid-infrared optical frequency combs: progress and applications (Invited)[J]. Infrared and Laser Engineering, 51, 20210969(2022).

[2] Cundiff S T, Ye J. Colloquium: Femtosecond optical frequency combs[J]. Reviews of Modern Physics, 75, 325-342(2003).

[3] Hänsch T W. Nobel Lecture: passion for precision[J]. Reviews of Modern Physics, 78, 1297-1309(2006).

[4] Wu G H, Shi L H, Li E G. Surface topography measurement technology based on optical frequency comb[J]. Laser & Optoelectronics Progress, 60, 0312013(2023).

[5] Diddams S A, Hollberg L, Mbele V. Molecular fingerprinting with the resolved modes of a femtosecond laser frequency comb[J]. Nature, 445, 627-630(2007).

[6] Thorpe M J, Moll K D, Jones R J et al. Broadband cavity ringdown spectroscopy for sensitive and rapid molecular detection[J]. Science, 311, 1595-1599(2006).

[7] Chang Z H, Corkum P. Attosecond photon sources: the first decade and beyond[J]. Journal of the Optical Society of America B, 27, B9-B17(2010).

[8] Tauser F, Leitenstorfer A, Zinth W. Amplified femtosecond pulses from an Er: fiber system: nonlinear pulse shortening and self-referencing detection of the carrier-envelope phase evolution[J]. Optics Express, 11, 594-600(2003).

[9] Timmers H, Kowligy A, Lind A et al. Molecular fingerprinting with bright, broadband infrared frequency combs[J]. Optica, 5, 727-732(2018).

[10] Saule T, Holzberger S, de Vries O et al. Phase-stable, multi-µJ femtosecond pulses from a repetition-rate tunable Ti∶Sa-oscillator-seeded Yb-fiber amplifier[J]. Applied Physics B, 123, 17(2017).

[11] Pronin O, Seidel M, Lücking F et al. High-power multi-megahertz source of waveform-stabilized few-cycle light[J]. Nature Communications, 6, 6988(2015).

[12] Parriaux A, Hammani K, Millot G. Two-micron all-fibered dual-comb spectrometer based on electro-optic modulators and wavelength conversion[J]. Communications Physics, 1, 17(2018).

[13] Muraviev A V, Smolski V O, Loparo Z E et al. Massively parallel sensing of trace molecules and their isotopologues with broadband subharmonic mid-infrared frequency combs[J]. Nature Photonics, 12, 209-214(2018).

[14] Lee K F, Hensley C J, Schunemann P G et al. Midinfrared frequency comb by difference frequency of erbium and thulium fiber lasers in orientation-patterned gallium phosphide[J]. Optics Express, 25, 17411-17416(2017).

[15] Zhou L, Liu Y, Xie G H et al. Mid-infrared optical frequency comb in the 2.7–4.0 μm range via difference frequency generation from a compact laser system[J]. High Power Laser Science and Engineering, 8, e32(2020).

[16] Ma T, Lu Q, Zhao C L et al. Mid-infrared DFG comb with broadband and wide tunable range based on all polarization-maintaining fibers[J]. Chinese Journal of Lasers, 50, 2301008(2023).

[17] Gaida C, Gebhardt M, Heuermann T et al. Ultrafast thulium fiber laser system emitting more than 1 kW of average power[J]. Optics Letters, 43, 5853-5856(2018).

[18] Adler F, Diddams S A. High-power, hybrid Er∶fiber/Tm∶fiber frequency comb source in the 2 μm wavelength region[J]. Optics Letters, 37, 1400-1402(2012).

[19] Heidt A M, Hodasi J M, Rampur A et al. Low noise all-fiber amplification of a coherent supercontinuum at 2 µm and its limits imposed by polarization noise[J]. Scientific Reports, 10, 16734(2020).

[20] Xing S D, Kowligy A S, Lesko D M B et al. All-fiber frequency comb at 2 µm providing 1.4-cycle pulses[J]. Optics Letters, 45, 2660-2663(2020).

[21] Cao S Y, Han Y, Ding Y J et al. Precise determination of characteristic laser frequencies by an Er-doped fiber optical frequency comb[J]. Chinese Physics B, 31, 074207(2022).

[22] Zuo A B, Li W B, Peng Y X et al. Research on frequency stabilization of modulation transfer spectroscopy[J]. Chinese Journal of Lasers, 32, 164-166(2005).