Spectroscopic, thermal and laser characteristics of Nd:LiLuF₄for 1314 nm laser

Abstract

Nd-doped LiLuF4 crystal was grown by the traditional Czochralski method. Room-temperature polarized spectroscopic characteristics of Nd3+ ions in LiLuF4 crystal were investigated. The maximum emission cross-sections are 5.45 × 10−20 cm2 at 1320 nm and 2.34 × 10−20 cm2 at 1313 nm for π-polarization and σ-polarization, respectively. The thermal expansion coefficient, specific heat, thermal diffusion coefficient and the thermal conductivity of Nd:LiLuF4 crystal were systematically studied, which, to the best of our knowledge, is the first time for this crystal thus far. Laser operation in an Nd:LiLuF4 single crystal at 1314 nm with laser-diode pumping was demonstrated. We obtained 3.7 W output power at 1314 nm with a slope efficiency of near 32%. The results of our study indicate that Nd:LiLuF4 crystal is a very promising crystal for application as a high-peak power laser.

Growth, optical characterization and evaluation of laser properties of Nd:LaF3 crystal

“…The peak absorption cross-sections around 793 nm was obtained to be 1.89 Â 10 À20 cm 2 with FWHM of 19 nm, which can be well adapted to commercially available high-power GaAlAs LDs. With the obtained JeO intensity parameters U t(t¼2, 4,6) , the branching ratios and radiative lifetime for the transition of 4 F 3/2 / 4 I 11/2 is calculated to be 49.6% and 567 ms, respectively. The peak emission cross-section was 2.09 Â 10 À2 0 cm 2 around 1063 nm with a broad FWHM of 35 nm, which shows capacity of the crystal in~1 mm tunable and ultrashort pulse laser applications.…”

“…Several oxide and fluoride crystals, such as YVO 4 , YAG and LiYF 4 , have been proposed for Nd doping, and some related studies have been carried out on the properties of these Nd-doped crystals [6e9]. Compared with oxides, fluoride crystals usually have high transparency in wider wavelength range and longer upper-level ( 4 F 3/2 ) lifetime for energy storage.…”

Polarized upconversion luminescence from a single LiLuF4:Yb3+/Er3+ microcrystal for orientation tracking

“…LiLuF 4 is a uniaxial crystal with a tetragonal structure (space group I4 1 /a) isomorphic to LiYF 4 and a single site symmetry of S 4 for all Lu 3+ ions [39][40][41][42]. It is an efficient host material for UCL of Ln 3+ dopants owing to its low phonon energy and high chemical stability [43,44].…”