[Study of spectral property of Er3+-doped TiO2]

Spectral property of Er3+-doped TiO2 prepared with gel method using absolute alcohol, glacial acetic acid and tetrabutyl titanate was studied. The Stokes emission spectra at 488 nm and upconversion emission spectra at 980 nm of the material were measured. In the visible range, green and red light was observed with green light corresponding to 2H(11/2), 4S(3/2)-->4I(15/2) transition of Er3+, and red light corresponding to 4F(9/2)-->4I(15/2) transition of Er3+. The green and red light are both two-phonon process from the curve of In Ivis-ln Iin, as the light intensity is directly proportional to the square of pump power. Elementary studies of the upconversion process were conducted.