[1] [1] LI L Q, KONG W J, CHEN F. Femtosecond laser-inscribed optical waveguides in dielectric crystals: A concise review and recent advances［J］. Advanced Photonics, 2022, 4: 024002.

[2] [2] DAVIS K M, MIURA K, SUGIMOTO N, et al. Writing waveguides in glass with a femtosecond laser［J］. Optics Letters, 1996, 21(21): 1729-1731.

[3] [3] CHEN F, DE ALDANA J R V. Optical waveguides in crystalline dielectric materials produced by femtosecond-laser micromachining［J］. Laser & Photonics Reviews, 2014, 8(2): 251-275.

[6] [6] WANG X Y, YU X M, BERG M J, et al. Curved waveguides in silicon written by a shaped laser beam［J］. Optics Express, 2021, 29(10): 14201-14207.

[7] [7] LI L Q, LI Z Q, NIE W J, et al. Femtosecond-laser-written S-curved waveguide in Nd: YAP crystal: Fabrication and multi-gigahertz lasing［J］. Journal of Lightwave Technology, 2020, 38(24): 6845-6852.

[8] [8] LONG X W, BAI J. Laser action from a femtosecond laser written Yb: Phosphate glass waveguide［J］. Optik, 2022, 249: 168308.

[10] [10] BIASETTI D, NEYRA E, VZQUEZ DE ALDANA J R, et al. Buried waveguides in Nd: YLF crystals obtained by femtosecond laser writing under double line approach［J］. Applied Physics A, 2013, 110(3): 595-599.

[13] [13] YU F, WANG L C, CHEN Y, et al. Polarization independent quantum devices with ultra-low birefringence glass waveguides［J］. Journal of Lightwave Technology, 2021, 39(5): 1451-1457.

[15] [15] SALTER P S, JESACHER A, SPRING J B, et al. Adaptive slit beam shaping for direct laser written waveguides［J］. Optics Letters, 2012, 37(4): 470-472.

[16] [16] HE F, XU H, CHENG Y, et al. Fabrication of microfluidic channels with a circular cross section using spatiotemporally focused femtosecond laser pulses［J］. Optics Letters, 2010, 35(7): 1106-1108.

[18] [18] TAN D Z, SUN X Y, QIU J R. Femtosecond laser writing low-loss waveguides in silica glass: Highly symmetrical mode field and mechanism of refractive index change［J］. Optical Materials Express, 2021, 11(3): 848.

[20] [20] SHAH L, ARAI A, EATON S, et al. Waveguide writing in fused silica with a femtosecond fiber laser at 522 nm and 1 MHz repetition rate［J］. Optics Express, 2005, 13(6): 1999-2006.

[21] [21] BISCH N, GUAN J, BOOTH M J, et al. Adaptive optics aberration correction for deep direct laser written waveguides in the heating regime［J］. Applied Physics A, 2019, 125(5): 364.

[22] [22] ROTH G L, ESEN C, HELLMANN R. Circular microchannels inside bulk polymethylmethacrylate generated by femtosecond laser using slit beam shaping［J］. Journal of Laser Applications, 2019, 31(2): 022603.

[23] [23] LIU D, LI Y, AN R, et al. Influence of focusing depth on the microfabrication of waveguides inside silica glass by femtosecond laser direct writing［J］. Applied Physics A, 2006, 84(3): 257-260.

[24] [24] ZHOU Y H, ZHANG Z H, WANG Y P, et al. Selective laser melting of typical metallic materials: An effective process prediction model developed by energy absorption and consumption analysis［J］. Additive Manufacturing, 2019, 25: 204-217.

[25] [25] ZHANG H B, EATON S M, HERMAN P R. Low-loss type Ⅱ waveguide writing in fused silica with single picosecond laser pulses［J］. Optics Express, 2006, 14(11): 4826.