Steinberg S, Göring R, Hennig T, Rasch A
Opt Lett. 1995 Apr 1;20(7):683-5. doi: 10.1364/ol.20.000683.
A quantitative comparison of the photorefractive effect in annealed proton-exchanged channel waveguides in MgO-doped and congruent LiNbO(3) at the wavelengths of 633 and 830 nm is presented. An accurate measurement technique is described to measure the refractive-index change as a function of time and the guided mode intensity for different wavelengths. The results show that doping with 7% MgO reduces the photorefractive effect at a wavelength of lambda = 633 nm by 2 orders of magnitude. The photorefractive effect in the doped substrate shows only a weak dependence on the guided power. Doping with 4 mol.% MgO has only little effect on the photorefractive effect compared with that on the congruent material. A reduced photovoltaic current is responsible for the small photorefractive effect in the 7 mol. %-doped substrate.
本文给出了在633和830nm波长下，掺氧化镁的同成分铌酸锂（LiNbO₃）中经退火处理的质子交换通道波导内光折变效应的定量比较。描述了一种精确的测量技术，用于测量不同波长下折射率随时间以及导模强度的变化。结果表明，掺杂7%的氧化镁可使波长λ = 633nm处的光折变效应降低两个数量级。掺杂衬底中的光折变效应仅对导波光功率有微弱依赖。与同成分材料相比，掺杂4mol.%的氧化镁对光折变效应影响很小。7mol.%掺杂衬底中光折变效应较小是由于光生伏打电流减小所致。
