[1] [1] Johnson E J, Kafalas J, Dyes W A. Appl. Phys. Lett., 1982, 40: 993.

[3] [3] Lindmayer J. Solid State Technology, 1988, 31(8): 135.

[4] [4] Cho Y, Kim D S, Choe B, et al. Phys. Rev. B, 1997, 56: R4375.

[6] [6] Lecointre, Bessiere, Bos, et al. J. Phys. Chem. C, 2011, 115: 4217.

[7] [7] Dorenbos P. Phys. Status Solidi B, 2005, 242(1): R7.

[8] [8] Carvalho J M, Rodrigues L C V, Felinto M C F C, et al. J. Mater. Chem. (submitted).

[9] [9] Van den Eeckhout K, Smert P F, Poelman D. Materials, 2010, 3: 2536.

[10] [10] Pan Z W, Lu Y Y, Liu F. Nat. Mater., 2012, 11: 58.

[11] [11] Yamashita S A, Ogawa N. Phys. Solidi B, 1989, 118(89).

[12] [12] Zhang Y, Wang B, Liu X, et al. J. Appl. Phys., 2010, 107: 103502.

[13] [13] Gedam S C, Dhoble S J. Journal of Luminescence, 2013, 141: 23.

[16] [16] Meijerin K A, Schipper W J, Blasse G. Journal of Physics D Applied Physics, 2000, 25(6): 997.

[17] [17] Jee S D, Park J K, Lee S H. J Mater. Sci., 2008, 41: 3139.

[18] [18] Jang H S, Jeon D Y. Appl. Phys. Lett., 2007, 90: 041906.

[19] [19] Hermi F Brito, Jorma Hls, Taneli Laamanen, et al. Optical Materials Express, 2012, 2(4): 371.

[20] [20] Chen R Y. Appl. Phys., 1969, (40): 570.