Growth and characterization of the spectra of EuAlO_3:Ti and GdAIO_3:Ti

Two titanium-doped perovskites, EuAlO_3 and GdAlO_3, have been grown by laser-heated pedestal growth as potential visible–near-infrared lasers. The absorption spectra of EuAlO_3:Ti and the lack of Ti^3+ fluorescence from this material indicate the dominance of a charge-transfer transition between titanium and europium. The spectra of GdAlO_3:Ti in the visible region are consistent with Ti^3+ in an octahedral field. The absence of the charge-transfer transitions in the spectra of GdAlO_3:Ti is due to the third ionization potential of Gd’s being approximately 4 eV smaller than that of Eu. GdA1O_3:Ti has potential as a tunable-laser material with a center wavelength of 610 nm.