[1] Steinmeyer G, Sutter D H, Gallmann L et al. Frontiers in ultrashort pulse generation: pushing the limits in linear and nonlinear optics[J]. Science, 286, 1507-1512(1999).

[2] Leone S R. McCurdy C W, Burgdörfer J, et al. What will it take to observe processes in ‘real time’?[J]. Nature Photonics, 8, 162-166(2014).

[3] Ancona A, Döring S, Jauregui C et al. Femtosecond and picosecond laser drilling of metals at high repetition rates and average powers[J]. Optics Letters, 34, 3304-3306(2009).

[4] Dawson J W, Messerly M J, Beach R J et al. Analysis of the scalability of diffraction-limited fiber lasers and amplifiers to high average power[J]. Optics Express, 16, 13240-13266(2008).

[5] Liu W, Liao R Y, Zhao J et al. Femtosecond Mamyshev oscillator with 10-MW-level peak power[J]. Optica, 6, 194-197(2019).

[6] Dubinskii M, Zhang J, Fromzel V et al. Low-loss ‘crystalline-core/crystalline-clad’ (C4) fibers for highly power scalable high efficiency fiber lasers[J]. Optics Express, 26, 5092-5101(2018).

[7] Mu X D, Meissner S, Meissner H et al. High efficiency Yb∶YAG crystalline fiber-waveguide lasers[J]. Optics Letters, 39, 6331-6334(2014).

[8] Mu X D, Meissner H, Lee H C et al. True crystalline fibers: double-clad LMA design concept of Tm∶YAG-core fiber and its mode simulation[J]. Proceedings of SPIE, 8237, 82373M(2012).

[9] Chen F. Optical waveguides in crystalline dielectric materials produced by femtosecond-laser micromachining[J]. Laser & Photonics Reviews, 8, 251-275(2014).

[10] Cheng D J, Hu X, Hui Y L et al. Design of large-core Yb∶YAG crystal waveguide[J]. Laser & Optoelectronics Progress, 56, 231401(2019).

[11] Cheng D J, Hu X, Lei H et al. Design and experimental verification of near diffraction-limited output of a large core size Yb∶YAG crystalline waveguide laser[J]. Optics Communications, 451, 307-310(2019).

[12] Xue K, Hu X, Cheng D J et al. Calculation and experimental verification of large core size Yb∶YAG crystalline waveguide with near-diffraction-limited laser output[J]. Acta Optica Sinica, 40, 1914002(2020).

[13] Hui Y L, Liu Q, Hu X et al. High efficiency active Q-switched laser operation with a large size rectangular core crystalline waveguide[J]. Optics Express, 29, 2099-2105(2021).

[14] Lei H, Liu Q, Wang Y et al. Passively Q-switched pulse laser with large core size crystal waveguide near diffraction-limit beam quality output[J]. Acta Optica Sinica, 41, 1214001(2021).

[15] Hönninger C, Paschotta R, Morier-Genoud F et al. Q-switching stability limits of continuous-wave passive mode locking[J]. Journal of the Optical Society of America B, 16, 46-53(1999).

[16] Taira T, Tulloch W M, Byer R L. Modeling of quasi-three-level lasers and operation of CW Yb∶YAG lasers[J]. Applied Optics, 36, 1867-1874(1997).