[1] [1] Bahtat A, Bouazaoui M, Bahtat M et al.. Fluorescence of Er3+ ions in TiO2 planar waveguides prepared by a sol-gel process. Opt. Commun., 1994, 111(1)：55～60

[2] [2] Benatsou M, Capoen B, Bouazaoui M et al.. Preparation and characterization of sol-gel derived Er3+∶Al2O3-SiO2 planar waveguides. Appl. Phys. Lett., 1997, 71(4):428～430

[3] [3] Polman A, Jacobson D C, Eaglesham D J et al.. Optical doping of waveguide materials by MeV Er implantation. J. Appl. Phys., 1991, 70(7):3778～3784

[4] [4] Kurokawa Y, Ishizaka T, Ikoma T et al.. Photo-properties of rare earth ion (Er3+, Eu3+ and Sm3+)-doped alumina films prepared by the sol-gel method. Chem. Phys. Lett., 1998, 287(6):737～741

[5] [5] van den Hoven G N, Snoek E, Polman A. Photoluminescence characterization of Er-implanted Al2O3 films. Appl. Phys. Lett., 1993, 62(24):3065～3067

[6] [6] Pillonnet A, Garapon C, Champeaux C et al.. Fluorescence of Cr3+ doped alumina optical waveguides prepared by pulsed laser deposition and sol-gel method. J. Lumin., 2000, 87～89(8):1087～1089

[7] [7] Yoldas B E. Alumina gels that form porous transparent Al2O3. J. Maters. Sci., 1975, 10(10):1856～1860

[8] [8] Cheong H, Cho W S, Ha J S et al.. Structural evolution of alumina membrane prepared on an alumina support using a sol-gel method. J. Alloys and Compounds., 1999, 290(2):304～309

[10] [10] MacKenzie K J D, Temuujin J, Smith M E et al.. Effect of mechanochemical activation on the thermal reactions of boehmite (γ-AlOOH) and γ-Al2O3. Thermochim. Acta., 2000, 359(1):87～94

[11] [11] Fu Q, Cao C B, Zhu H S. Preparation of alumina films from a new sol-gel route. Thin Solid Film, 1999, 348(1):99～102

[12] [12] van den Hoven G N, Snoeks E, Polman A et al.. Upconversion in Er-implanted Al2O3 waveguides. J. Appl. Phys., 1996, 79(3):1258～1266