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

• A β′-Yb:Gd2(MoO4)3 crystal was grown successfully by the Czochralski method.
• The intensity of SHG of β′-Yb:Gd2 (MoO4)3 is about 3 times as large as that of KDP.
• β′-Yb:Gd2(MoO4)3 has negative thermal expansion and moderate thermal conductivity.
• The crystal is suitable for LD pumping and easy to realize laser oscillation.
• β′-Yb:Gd2(MoO4)3 is a promising self-frequency doubling laser crystal.

A β′-Yb3+:Gd2 (MoO4)3 crystal with dimensions of 22×22×25 mm3 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 14.7×10−6 K−1, 13.5×10−6 K−1 and −20.1×10−6 K−1 along a-, b- and c-axes, respectively. The thermal conductivity along the c-axis is 1.44 W/m K at room temperature. The absorption cross section at 977 nm is 0.48×10−20 cm2 with full width at half maximum of 20 nm. The emission cross section at 1030 nm is 1.13×10−20 cm2. The fluorescence lifetime is 722 μs. The results indicate that β′-Yb:Gd2(MoO4)3 crystal is a promising candidate of self-frequency doubling laser material.