【摘要】 在室温下,测量了采用Czochralski方法生长的as-grown和经退火处理的Z切Er3+／Yb3+共掺同成 分LiNbO3晶体的a偏振吸收光谱(300-1 650 nm)。运用Judd-Ofelt理论对该晶体中Er3+的光谱特性进行 了分析。由所测得的吸收系数的积分计算得到了从基态到激发态的若干个主要的电子跃迁强度实验值。利 用最小二乘法确定出Er3+／Yb3+共掺LiNbO3晶体中Er3+的Judd-Ofelt参数。进而确定了自发辐射概率,从 激发态能级到其各个下能级的荧光分支比以及能级辐射寿命。此外,还讨论了Yb3+的共掺和退火处理对 LiNbO3晶体中Er3+光谱特性的影响。更多还原

【Abstract】 At room temperature, α-polarized absorption spectra of as-grown and annealed Er3 + /Yb3+ co-doped, Z-cut LiNbO3 single crystals, grown by using Czochralski method, were measured in the wavelength range of 300-1 650 nm. The spectroscopic properties of Er3+ were analysed by using Judd-Ofelt theory. The experimental values of the electron transition strengths of several major transitions from the ground state to excited-state manifolds were evaluated from the measured integrated absorption coefficients of Er3+. The Judd-Ofelt parameters were determined by using least square method. According to the fitted Judd-Ofelt parameters, the spontaneous emission rates, the fluorescence branch ratios from the excited-state manifolds J to the lower-lying manifolds J’, as well as the radiative lifetimes of the excited states were numerically calculated. In addition, Yb3+ co-doping and thermal anneal effects on the spectroscopic properties of Er3+ were also considered in this work.更多还原