Novel Nd3+ and Ho3+ co-doped multifunctional CeF3 crystal for laser and magneto-optical applications

In this study, a 1.5 at.% Nd3+ and 0.5 at.% Ho3+ co-doped CeF3 (Nd,Ho:CeF3) single crystal was successfully grown by the vertical Bridgman method. The absorption and fluorescence characteristics of the fabricated crystal were evaluated. The spectroscopic properties of the Nd,Ho:CeF3 crystal were investigated based on the Judd–Ofelt (J–O) theory. The parameters Ω2, Ω4, and Ω6 of Ho3+ were fitted as 0.338×10−20, 0.731×10−20, and 0.350×10−20 cm2, respectively. The fluorescence lifetimes centered at 1064 and 1970 nm for Nd3+ and Ho3+ were 261 and 47 μs, respectively. Notably, the magneto-optical performance of the Nd,Ho:CeF3 crystal was investigated for the first time. The measured Verdet constants of Nd,Ho:CeF3 at 532, 632.8, 1064, 1310, and 1550 nm were 228.0, 154.7, 42.4, 29.1, and 18.5 rad·T−1·m−1, respectively, which were significantly higher than those of pure CeF3 and traditional Tb3Ga5O12. The results demonstrated that Nd,Ho:CeF3 crystals can be applied in both lasers and magneto-optical devices.