[1] [1] DOUALAN J L, CAMY P, MONCORG R, et al. Latest developments of bulk crystals and thin films of rare-earth doped CaF2 for laser applications[J]. Journal of Fluorine Chemistry, 2007, 128(4): 459-464.

[2] [2] MERONI C, BRAUD A, DOUALAN J L, et al. Spectroscopy and laser gain measurements of CaF2∶Nd, X3+, Z3+ (X, Z=Gd, La, Ce, Y, Lu, Sc) crystals for broadband lasers applications[J]. Journal of Luminescence, 2022, 252: 119336.

[3] [3] KATO T, NAKAUCHI D, KAWAGUCHI N, et al. Dy-concentration dependence on dosimetric properties of CaF2 transparent ceramics[J]. Optical Materials, 2022, 132: 112785.

[4] [4] BALABANOV S, PERMIN D, EVSTROPOV T, et al. Hot pressing of Yb∶Y2O3 laser ceramics with LiF sintering aid[J]. Optical Materials, 2021, 119: 111349.

[5] [5] YIN D L, WANG J, WANG Y, et al. Fabrication of Er∶Y2O3 transparent ceramics for 2.7 m mid-infrared solid-state lasers[J]. Journal of the European Ceramic Society, 2020, 40(2): 444-448.

[6] [6] LIU Z Y, TOCI G, PIRRI A, et al. Fabrication, microstructures, and optical properties of Yb∶Lu2O3 laser ceramics from co-precipitated nano-powders[J]. Journal of Advanced Ceramics, 2020, 9(6): 674-682.

[7] [7] AUBRY P, BENSALAH A, GREDIN P, et al. Synthesis and optical characterizations of Yb-doped CaF2 ceramics[J]. Optical Materials, 2009, 31(5): 750-753.

[8] [8] LYBERIS A, PATRIARCHE G, GREDIN P, et al. Origin of light scattering in ytterbium doped calcium fluoride transparent ceramic for high power lasers[J]. Journal of the European Ceramic Society, 2011, 31(9): 1619-1630.

[9] [9] AKCHURIN M, BASIEV T, DEMIDENKO A, et al. CaF2∶Yb laser ceramics[J]. Optical Materials, 2013, 35(3): 444-450.

[10] [10] YANG Y, LI W W, MEI B C, et al. Synthesis and enhanced upconversion luminescence upon two-wavelength excitation of Er3+∶CaF2 transparent ceramics[J]. Journal of Luminescence, 2019, 213: 504-509.

[11] [11] YI G Q, LI W W, SONG J H, et al. Preparation and characterizations of Pr3+∶CaF2 transparent ceramics with different doping concentrations[J]. Ceramics International, 2019, 45(3): 3541-3546.

[12] [12] IKESUE A, AUNG Y L. Ceramic laser materials[J]. Nature Photonics, 2008, 2(12): 721-727.

[13] [13] FANG Z Q, SUN D L, LUO J Q, et al. Thermal analysis and laser performance of a GYSGG/Cr, Er, Pr∶GYSGG composite laser crystal operated at 2.79 m[J]. Optics Express, 2017, 25(18): 21349-21357.

[14] [14] MA C Y, ZHU J F, LIU K, et al. Longitudinally diode-pumped planar waveguide YAG/Yb∶LuAG/YAG ceramic laser at 1030.7 nm[J]. Optics Letters, 2016, 41(14): 3317-3319.

[16] [16] GOLDSTEIN A, KRELL A. Transparent ceramics at 50: progress made and further prospects[J]. Journal of the American Ceramic Society, 2016, 99(10): 3173-3197.

[17] [17] LIU Z D, MEI B C, SONG J H, et al. Microstructure and optical properties of hot-pressed Er∶CaF2 transparent ceramics[J]. Journal of Alloys and Compounds, 2015, 646: 760-765.

[18] [18] LIU Z D, MEI B C, SONG J H, et al. Influence of Yb concentration on the optical properties of CaF2 transparent ceramics codoped with Er and Yb[J]. Journal of the American Ceramic Society, 2015, 98(12): 3905-3910.

[19] [19] LIU Z D, JIA M Y, YI G Q, et al. Fabrication and microstructure characterizations of transparent Er∶CaF2 composite ceramic[J]. Journal of the American Ceramic Society, 2019, 102(1): 285-293.

[20] [20] PANDURANGAPPA C, LAKSHMINARASAPPA B N, NAGABHUSHANA B M. Synthesis and characterization of CaF2 nanocrystals[J]. Journal of Alloys and Compounds, 2010, 489(2): 592-595.

[21] [21] APETZ R, VAN BRUGGEN M P B. Transparent alumina: a light-scattering model[J]. Journal of the American Ceramic Society, 2003, 86(3): 480-486.

[22] [22] CHEN C F, DOTY F P, HOUK R J T, et al. Characterizations of a hot-pressed polycrystalline spinel: Ce scintillator[J]. Journal of the American Ceramic Society, 2010, 93(8): 2399-2402.

[23] [23] TSUKUMA K, YAMASHITA I, KUSUNOSE T. Transparent 8 mol% Y2O3-ZrO2 (8Y) ceramics[J]. Journal of the American Ceramic Society, 2008, 91(3): 813-818.