Synthesis and characterization of diffusion-doped Cr2+:ZnSe and Fe2+:ZnSe

This paper provides a detailed description of the preparation and characterization of diffusion-doped Cr2+:ZnSe and Fe2+:ZnSe. In the experiments, Cr2+:ZnSe samples with peak absorption coefficients (1775 nm) of as high as 74 cm−1 and fairly good spatial uniformity were obtained. In the case of Fe2+:ZnSe, samples with a maximum absorption coefficient of 11.6 cm−1 at 2400 nm were synthesized. A three-dimensional analytical diffusion model was further developed to determine the diffusion coefficient D from absorption data. At 1000 °C, D was determined to be 5.4 × 10−10 cm2/s and 7.95 × 10−10 cm2/s for Cr2+:ZnSe and Fe2+:ZnSe, respectively. In the case of Cr2+:ZnSe, we employed an alternative technique to determine the diffusion coefficient from position-dependent absorption data taken with a Cr4+:YAG laser. With this method, the temperature variation of D was further measured in the 800–1100 °C temperature ranges.