Growth and Spectroscopic Characteristics of Yb3+:LiGd(WO4)2 Crystal

The Yb3+:LiGd(WO4)(2) crystal with the dimension of Phi 15x35 mm(3) was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3+ in Yb3+:LiGd(WO4)(2) crystal were investigated. The Yb3+.:LiGd(WO4)(2) crystal exhibits a broad absorption band centered near 975 nm with the linewidths of 16 and 11 nm and maximal absorption cross-section of 3.60 x 10(-20) and 2.90 x 10(-20) cm(2) for pi- and sigma-polarization, respectively. The emission broadband has an FWHM of 47 and 45 nm with the emission cross sections of 3.92 x 10(-20) and 3.34 x 10(-20) cm(2) at 1020 nm for pi- and sigma-polarization, respectively. The measured fluorescence lifetime is 398 mu s. The blue light emission around 480 nm through cooperative upconversion from the de-excitation of excited Yb3+-Yb3+ pairs at 4 K was observed under 932-nm excitation and demonstrated.