[1] Teets R, Eckstein J, Hänsch T W. Coherent two-photon excitation by multiple light pulses [J]. Physical Review Letters, 1977, 38(14): 760-764. doi:  10.1103/PhysRevLett.38.760
[2] Diddams S A. The evolving optical frequency comb [J]. Journal of the Optical Society of America B, 2010, 27(11): B51-B62. doi:  10.1364/JOSAB.27.000B51
[3] Spence D E, Kean P N, Sibbett W. 60-fsec pulse generation from a self-mode-locked Ti sapphire laser [J]. Optics Letters, 1991, 16(1): 42-44. doi:  10.1364/OL.16.000042
[4] Tamura K, Ippen E P, Haus H A, et al. 77-fs pulse generationfrom astretched-pulse mode-locked all-fiber ring laser [J]. Optics Letters, 1993, 18(13): 1080-1082. doi:  10.1364/OL.18.001080
[5] Kippenberg T J, Holzwarth R, Diddams S A. Microresonator-based optical frequency combs [J]. Science, 2011, 332(6029): 555-559. doi:  10.1126/science.1193968
[6] Kippenberg T J, Gaeta A L, Lipson M, et al. Dissipative Kerr solitons in optical microresonators [J]. Science, 2018, 361(6402): 8083. doi:  10.1126/science.aan8083
[7] Shen B, Chang L, Liu J, et al. Integrated turnkey soliton microcombs [J]. Nature, 2020, 582(18): 365-369.
[8] Vahala K J. Optical microcavities [J]. Nature, 2003, 424(6950): 839-646. doi:  10.1038/nature01939
[9] Kippenberg T J, Spillane S M, Vahala K J. Kerr-nonlinearity optical parametric oscillation in an ultrahigh-Q toroid microcavity [J]. Physical Review Letters, 2004, 93(8): 083904. doi:  10.1103/PhysRevLett.93.083904
[10] Del'Haye P, Schliesser A, Arcizet O, et al. Optical frequency comb generation from a monolithic microresonator [J]. Nature, 2007, 450(7173): 1214-1217. doi:  10.1038/nature06401
[11] Herr T, Brasch V, Jost J D, et al. Temporal solitons in optical microresonators [J]. Nature Photonics, 2014, 8: 145-152. doi:  10.1038/nphoton.2013.343
[12] Savchenkov A A, Ilchenko V S, Teodoro F D, et al. Generation of Kerr combs centered at 4.5 μm in crystalline microresonators pumped with quantum-cascade lasers [J]. Optics Letters, 2015, 40: 3468-3471. doi:  10.1364/OL.40.003468
[13] Fujii S, Tanaka S, Fuchida M, et al. Octave-wide phase-matched four-wave mixing in dispersion engineered crystalline microresonators [J]. Optics Letters, 2019, 44: 3146-3149. doi:  10.1364/OL.44.003146
[14] Lucas E, Brochard P, Bouchand R, et al. Ultralow-noise photonic microwave synthesis using a soliton microcomb-based transfer oscillator [J]. Nature Communications, 2020, 11: 374. doi:  10.1038/s41467-019-14059-4
[15] Lucas E, Lihachev G, Bouchand R, et al. Spatial multiplexing of soliton microcombs [J]. Nature Photonics, 2018, 12: 699-705. doi:  10.1038/s41566-018-0256-7
[16] Chiasera A, Dumeige Y, Féron P, et al. Spherical whispering-gallery mode microresonators [J]. Laser & Photonics Review, 2010, 4(3): 457-482.
[17] Coen S, Randle H G, Sylvestre T, et al. Modeling of octave-spanning Kerr frequency combs using a generalized mean-field Lugiato–Lefever model [J]. Optics Letters, 2013, 38(1): 37-39. doi:  10.1364/OL.38.000037
[18] Wang Mengyu, Yang Yu, Wu Tao, et al. Fabrication and resonance characteristic analysis of spheroid Calcium Fluoride millimeter crystalline microcavity [J]. Acta Optica Sinica, 2021, 41(8): 0823019. (in Chinese) doi:  10.3788/AOS202141.0823019
[19] Lu X, Xue C, Wang Y, et al. Fabrication and test of millimeter-size CaF2 disk resonator [J]. Infrared and Laser Engineering, 2015, 44(10): 3049-3054. (in Chinese) doi:  10.3969/j.issn.1007-2276.2015.10.031
[20] Herr T, Hartinger K, Riemensberger, et al. Universal formation dynamics and noise of Kerr-frequency combs in microresonators [J]. Nature Photonics, 2012, 6: 480-487. doi:  10.1038/nphoton.2012.127
[21] Yoshitomo O, Yu M, Vivek V. Competition between Raman and Kerr effects in microresonator comb generation [J]. Optics Letters, 2017, 42(14): 2786-2789. doi:  10.1364/OL.42.002786
[22] Jiang X, Yang L. Opto-thermal dynamics in whispering-gallery microresonators [J]. Light: Science & Applications, 2020, 9: 24.