Growth, thermal conductivity, spectra, and 2 µm continuous-wave characteristics of Tm3+, Ho3+ co-doped LaF3 crystal

Abstract

Abstract The Tm3+ and Ho3+ ions co-doped LaF3 crystal was grown successfully by the Bridgman method for the first time. X-ray diffraction, thermal conductivity, absorption, and fluorescence properties were investigated systematically. The thermal conductivity is 1.99 W/(mK) at room temperature. The absorption cross-section at 792 nm and emission cross-section at 1987 nm are 0.18 × 10 − 20 cm2 and 0.32 × 10 − 20 cm 2 , respectively. The Tm,Ho:LaF3 crystal exhibits wide absorption band (38 nm) and emission band (140 nm), as well as long fluorescence lifetime (17.56 ms). With a 10-mm-long sample, the output power of 574 mW at 2047 nm was obtained for the incident power of 3.53 W with a slope efficiency of 18.5%. It can be proposed that Tm,Ho:LaF3 crystal can be a potential material for LD-pumped tunable and ultra-short pulse laser applications operating at around 2 μ m .