[1] Shen D Y, Fan D Y[M]. Mid-infrared lasers, 1-9(2015).

[2] Hu M L, Cai Y. Research progress on mid-infrared ultrafast fiber laser[J]. Chinese Journal of Lasers, 47, 0500009(2020).

[3] Truong V G, Ham B S, Jurdyc A M et al. Relaxation properties of rare-earth ions in sulfide glasses: experiment and theory[J]. Physical Review B, 74, 184103(2006).

[4] Kang M Q, Deng Y, Yan X W et al. A compact and efficient 4.25 μm BaGa4Se7 optical parametric oscillator[J]. Chinese Optics Letters, 17, 121402(2019).

[5] Peng Y P, Jiang B X, Fan J T et al. Review of mid-infrared laser materials directly pumped by laser-diode[J]. Laser & Optoelectronics Progress, 52, 020001(2015).

[6] Sun X, Han L, Wang K Q. Progress in directly pumping of mid-infrared solid-state lasers[J]. Laser & Optoelectronics Progress, 54, 050007(2017).

[7] Majewski M R, Woodward R I, Jackson S D. Dysprosium mid-infrared lasers: current status and future prospects[J]. Laser & Photonics Reviews, 14, 1900195(2020).

[8] Majewski M R, Jackson S D. Highly efficient mid-infrared dysprosium fiber laser[J]. Optics Letters, 41, 2173-2176(2016).

[9] Majewski M R, Woodward R I, Jackson S D. Dysprosium-doped ZBLAN fiber laser tunable from 2.8 μm to 3.4 μm, pumped at 1.7 μm[J]. Optics Letters, 43, 971-974(2018).

[10] Woodward R I, Majewski M R, Bharathan G et al. Watt-level dysprosium fiber laser at 3.15 μm with 73% slope efficiency[J]. Optics Letters, 43, 1471-1474(2018).

[11] Fortin V, Jobin F, Larose M et al. 10-W-level monolithic dysprosium-doped fiber laser at 3.24 μm[J]. Optics Letters, 44, 491-494(2019).

[12] Wang Y C, Jobin F, Duval S et al. Ultrafast Dy 3+∶fluoride fiber laser beyond 3 μm[J]. Optics Letters, 44, 395-398(2019).

[13] Qu C B, Kang M Q, Xiang X J et al. Theoretical study of 4.3 μm dual-wavelength pumped Dy∶InF3 high-energy mid-infrared fiber lasers[J]. Chinese Journal of Lasers, 47, 0801003(2020).

[14] Quimby R S, Shaw L B, Sanghera J S et al. Modeling of cascade lasing in Dy∶chalcogenide glass fiber laser with efficient output at 4.5 μm[J]. IEEE Photonics Technology Letters, 20, 123-125(2008).

[15] Sujecki S, Sójka L. Bere -Pawlik E, et al. Modelling of a simple Dy 3+ doped chalcogenide glass fibre laser for mid-infrared light generation[J]. Optical and Quantum Electronics, 42, 69-79(2010).

[16] Falconi M C, Palma G, Starecki F et al. Design of an efficient pumping scheme for mid-IR Dy 3+∶Ga5Ge20Sb10S65 PCF fiber laser[J]. IEEE Photonics Technology Letters, 28, 1984-1987(2016).

[17] Xiao X S, Xu Y T, Guo H T et al. Theoretical modeling of 4.3 μm mid-infrared lasing in Dy 3+-doped chalcogenide fiber lasers[J]. IEEE Photonics Journal, 10, 1501011(2018).

[18] Jackson S D, Pollnau M, Li J F. Diode pumped erbium cascade fiber lasers[J]. IEEE Journal of Quantum Electronics, 47, 471-478(2011).

[19] Sulc J, Jelínková H, Doroshenko M E et al. Dysprosium-doped PbGa2S4 laser excited by diode-pumped Nd∶YAG laser[J]. Optics Letters, 35, 3051-3053(2010).

[20] Jelínková H, Doroshenko M E, Jelínek M et al. Dysprosium-doped PbGa2S4 laser generating at 4.3 μm directly pumped by 1.7 μm laser diode[J]. Optics Letters, 38, 3040-3043(2013).

[21] Jelinkova H, Doroshenko M E, Osiko V V et al. Dysprosium thiogallate laser: source of mid-infrared radiation at 2.4, 4.3, and 5.4 μm[J]. Applied Physics A, 122, 738-741(2016).

[22] Shayeganrad G, Mashhadi L. Efficient analytic model to optimum design laser resonator and optical coupling system of diode-end-pumped solid-state lasers: influence of gain medium length and pump beam M2 factor[J]. Applied Optics, 47, 619-627(2008).

[23] Chen Y Q, Wang J H[M]. Theory of laser, 122-127(1992).

[24] Morrison D D, Riley J D, Zancanaro J F. Multiple shooting method for two-point boundary value problems[J]. Communications of the ACM, 5, 613-614(1962).

[25] Quimby R S, Saad M. Pathways to a 4 μm Dy 3+ fluoride glass fiber laser. [C]∥Lasers Congress 2016 (ASSL, LSC, LAC), October 30-November 3, 2016, Boston, Massachusetts. Washington, D.C.: OSA, 34(2016).

[26] Flórez A, Jerez V A[J]. Flórez M. Optical transitions probabilities of Dy ³+ ions in fluoroindate glass. Journal of Alloys , Compounds, 303/304, 355-359(2000).