掺铒近化学计量比铌酸锂晶体的生长与光谱性质

Crystal Growth and Optical Properties of Er-doped Near Stoichiometric Lithium Niobate

利用提拉法,在富锂熔体中生长了质量良好的掺铒近化学计量比铌酸锂单晶,生长的晶体尺寸为φ35×25mm,测量了晶体的室温吸收谱,并根据Judd-Ofelt理论,拟合出晶体场唯象强度参数:Ω2=5.37×10-20cm2,Ω4=2.98×10-20cm2,Ω6=1.92×10-20cm2。计算了各能级的跃迁辐射几率AJ,J',振子强度PJ,J',辐射寿命τ,荧光分支比βJ'等,并根据这些光学参量讨论了该晶体的部分性能和应用前景。

Er-doped near stoichiometric lithium niobate （Er：SLN） crystal with good optical quality has been grown by Czochralski method. The as-grown crystal is 35mm in diameter and 25mm in length. When the Judd-Ofelt theory of parity-forbidden electric-dipole transitions of rare earth ions on noncentrosymmetric sites is applied to Er： NSLN, it results in a good fit on the absorption of the crystal. The three intensity parameters Ω1 are fitted at t = 2, 4, 6 respectively, Ω2 = 5. 37 × 10^-20cm^2, n4 = 2.98× 10^-20cm^2 ,Ω6 = 1.92 × 10^-20cm^2. The spectral parameters radiative transition probabilities AJ,J′, oscillator strengths PJ,J′, the radiative lifetime τ and the fluorescence branch ratio βj are also obtained. The result of this experiment is dicussed.