Temperature and concentration dependence of spectroscopic properties of Nd3+-doped yttrium aluminum garnet crystal

Abstract The optical absorption spectra of yttrium aluminum garnet (YAG) crystals doped with Nd 3+ ions with different concentrations (0.6 at%, 1.0 at%, 1.2 at%) at the temperature range from 300 K to 500 K have been measured. The calculated Judd–Ofelt (JO) parameters Ω t ( t =2, 4, 6) based on the spectra have been used to predict the radiative transition probabilities, branching ratios and radiative lifetimes of the transitions from 4 F 3/2 level to the lower levels ( 4 I 13/2 , 4 I 11/2 , 4 I 9/2 ) at each concentration and temperature. The three JO parameters Ω t ( t =2, 4, 6), according to the calculation, decrease with the increasing doped concentration at each temperature. The JO parameters Ω 2 and Ω 4 increase, while the parameter Ω 6 decreases with the increasing temperature at each concentration. The branching ratios and radiative transition probabilities of the transitions from the 4 F 3/2 level to 4 I 13/2 and 4 I 11 /2 levels decrease, while the transition from the 4 F 3/2 level to 4 I 9/2 level increases with the increasing temperature. The obtained results at each concentration and temperature are discussed.