Influence of Factors on the Growth of the Er3+/Tm3+-Codoped LiNbO3 Crystal by Er3+/Tm3+ Codiffusion

Abstract

The influence of factors on the growth of the Er3+/Tm3+-codoped LiNbO3 (LN) crystal by codiffusion of stacked Er and Tm metal thin films was studied. These factors include the thicknesses and the coating sequence of the Er and Tm metal films, and the growth is characterized by the diffusivity and solubility. To achieve the goal, Er3+/Tm3+-codoped LN crystals were grown by codiffusion in air at 1130 °C of stacked Er and Tm metal thin films coated onto the surface of Z-cut congruent LN plates. The metal films have different thicknesses and coating sequences. After the growth, the Er3+ and Tm3+ profiles were analyzed by secondary ion mass spectrometry. The Er3+/Tm3+ diffusivity and surface concentration were obtained from the measured profiles. The diffusivity is influenced by neither the thickness nor the coating sequence of metal films. The solubility consists of Er3+ and Tm3+ components, and the two components equal the respective concentrations in the diffusion reservoir and change with the initial metal...