[1] F Ahmed, M S Ahsan, M S Lee, M B G Jun. Near-field modification of femtosecond laser beam to enhance single-shot pulse filamentation in glass medium. Appl Phys A, 114, 1161-1165(2014).

[2] T E Lanier, J R Gulley. Nonlinear space-time focusing and filamentation of annular femtosecond pulses in dielectrics. J Opt Soc Am B, 33, 292-301(2016).

[3] P Masselin, D le Coq, E Bychkov, E Lépine, C Lin et al. Laser filamentation in chalcogenide glass. Proc SPIE, 7993, 79931B(2011).

[4] Q Yang, L F Ji, B Xu, T Y Yan, W H Wang et al. Picosecond laser microfabrication of infrared antireflective functional surface on As₂Se₃ glass. Opto-Electron Eng, 44, 1200-1209(2017).

[5] R Zhou, S D Lin, Y Ding, H Yang, K Ong et al. Enhancement of laser ablation via interacting spatial double-pulse effect. Opto-Electron Adv, 1, 180014(2018).

[6] A Couairon, A Mysyrowicz. Femtosecond filamentation in transparent media. Phys Rep, 441, 47-189(2007).

[7] J Galinis, G Tamošauskas, I Gražulevičiūtė, V Keblytė, V Jukna et al. Filamentation and supercontinuum generation in solid-state dielectric media with picosecond laser pulses. Phys Rev A, 92, 1-5(2015).

[8] Z Liu, X Lu, Q Liu, S Sun, L Li et al. Ultraviolet conical emission produced by high-power femtosecond laser pulse in transparent media. Appl Phys B, 108, 493-500(2012).

[9] M Durand, A Jarnac, A Houard, Y Liu, S Grabielle et al. Self-guided propagation of ultrashort laser pulses in the anomalous dispersion region of transparent solids: a new regime of filamentation. Phys Rev Lett, 110, 115003(2013).

[10] C Javaux Léger, K Mishchik, O Dematteo-Caulier, S Skupin, B Chimier et al. Effects of burst mode on transparent materials processing. Proc SPIE, 9351, 93510M(2015).

[11] L F Ji, , T Y Yan, W H Wang, T R Wang et al. Research progress of ultrafast laser industrial applications based on filamentation. Opto-Electron Eng, 44, 851-861(2017).

[12] J R Gulley, J X Liao, T E Lanier. Plasma generation by ultrashort multi-chromatic pulses during nonlinear propagation. Proc SPIE, 8972, 89720T(2014).

[13] J R Gulley, T E Lanier. Model for ultrashort laser pulse-induced ionization dynamics in transparent solids. Phys Rev B, 90, 155119(2014).

[14] B C Stuart, M D Feit, S Herman, A M Rubenchik, B W Shore et al. Optical ablation by high-power short-pulse lasers. J Opt Soc Am B, 13, 459-468(1996).

[16] C Ferris, C W Wang, Q Z Zhao, J Qian, Y B Li, G D Wang et al. Propagation of focused ultrashort pulse laser during micromachining of sapphire. Proc SPIE, 9532, 953200(2015).

          15FerrisCTheoretical modeling of laser-induced absorption phenomena in optical materials (University of Nebraska, Lincoln, Nebraska, 2014) Ferris C. Theoretical modeling of laser-induced absorption phenomena in optical materials (University of Nebraska, Lincoln, Nebraska, 2014).

[17] A Benayas, D Jaque, B McMillen, K P Chen. Thermal stability of microstructural and optical modifications induced in sapphire by ultrafast laser filamentation. J Appl Phys, 107, 033522(2010).

[18] R DeSalvo, A A Said, D J Hagan, E W Van Stryland, M Sheik-Bahae. Infrared to ultraviolet measurements of two-photon absorption and n₂ in wide bandgap solids. IEEE J Quantum Electron, 32, 1324-1333(1996).

[19] E Arola. Theoretical studies on multiphoton absorption of ultrashort laser pulses in sapphire. IEEE J Quantum Electron, 50, 709-720(2014).

[20] J M Liu. Simple technique for measurements of pulsed Gaussian-beam spot sizes. Opt Express, 7, 196-198(1982).

[21] L V Keldysh. Ionization in the field of a strong electromagnetic wave. Sov Phys JETP, 20, 1307-1314(1965).

[22] D G Papazoglou, I Zergioti, S Tzortzakis, G Sgouros, G Maravelias et al. Sub-picosecond ultraviolet laser filamentation-induced bulk modifications in fused silica. Appl Phys A, 81, 241-244(2005).

[23] [23] LottiAPulse shaping and ultrashort laser pulse filamentation for applications in extreme nonlinear optics (University of Insubria, Insubria, 2012) Lotti A. Pulse shaping and ultrashort laser pulse filamentation for applications in extreme nonlinear optics (University of Insubria, Insubria, 2012).

[24] A Couairon, L Sudrie, M Franco, B Prade, A Mysyrowicz. Filamentation and damage in fused silica induced by tightly focused femtosecond laser pulses. Phys Rev B, 71, 125435(2005).

[25] M T Wu, B Guo, Q L Zhao, R W Fan, Z W Dong et al. The influence of the focus position on laser machining and laser micro-structuring monocrystalline diamond surface. Opt Lasers Eng, 105, 60-67(2018).

[26] A Saliminia, N T Nguyen, S L Chin, R Vallée. The influence of self-focusing and filamentation on refractive index modifications in fused silica using intense femtosecond pulses. Opt Commun, 241, 529-538(2004).

[27] M S Liao, W Q Gao, T L Cheng, Z C Duan, X J Xue et al. Filamentation and supercontinuum generation in tellurite glass. Proc SPIE, 8621, 86211O(2013).