β′-Yb3+:Gd2(MoO4)3 crystal – A promising self-frequency doubling laser material

Abstract

A β′-Yb3+:Gd2 (MoO4)3 crystal with dimensions of 22×22×25mm3 was grown successfully by the Czochralski method. Its relative efficiency of second harmonic generation was measured by Kurtz power method, the intensity is about 3 times as large as that of KH2PO4 crystal. The thermal expansion coefficients of the crystal are 14.7×10−6K−1, 13.5×10−6K−1 and −20.1×10−6K−1 along a-, b- and c-axes, respectively. The thermal conductivity along the c-axis is 1.44W/mK at room temperature. The absorption cross section at 977nm is 0.48×10−20cm2 with full width at half maximum of 20nm. The emission cross section at 1030nm is 1.13×10−20cm2. The fluorescence lifetime is 722μs. The results indicate that β′-Yb:Gd2(MoO4)3 crystal is a promising candidate of self-frequency doubling laser material.