Crystal growth, spectral properties, and continuous wave laser operation of Nd:GdNbO4

Abstract

Nd:GdNbO4 crystal was grown successfully by the Czochralski (CZ) method. The continuous wave (CW) laser operation of Nd:GdNbO4 crystal at 1066 nm was reported for the first time. A maximum output power of 1.076 W with the incident power of 3.28 W was successfully obtained, corresponding to an optical-to-optical conversion efficiency of 32.8% and a slope efficiency of 35.3%. The absorption and fluorescence spectra of the crystal were measured at room temperature. By using the Judd-Ofelt approach, the intensity parameters were calculated to be 6.13 × 10−20, 1.56 × 10−20, and 2.81 × 10−20 cm2, respectively. The large absorption cross section (9.5 × 10−20 cm2) and broad absorption band (5 nm) at around 808 nm indicates that Nd:GdNbO4 crystal can be pumped efficiently by laser diodes (LD). The small emission cross section (9.3 × 10−20 cm2) and relatively long fluorescence lifetime (178 μs) of Nd3+ demonstrate good energy capacity of Nd:GdNbO4. All the results show that Nd:GdNbO4 crystal is a promising novel laser crystal suitable for LD pumping.