离子注入损伤层调控的周期极化KTiOPO4波导制备与特性研究

Periodically poled KTiOPO4 waveguides are widely used in optical parametric oscillation, optical parametric amplification, frequency doubling and all-optical wavelength conversion. KTiOPO4 waveguide with ferroelectric domain inverted can be formed by ion exchange; however, the depth of ferroelectric domain inversion is smaller than the depth of waveguide, which means that the light can't be circumscribed within the domain inversion region completely. Lattice damage layer with controllable depth can be formed by ion implantation, which can control the ion exchange depth effectively. In this project, firstly, the ion implanted damage layer will act as a barrier layer of ion exchange; secondly, periodically patterns can be fabricated by combining photo mask with metal coating; thirdly, ferroelectric domain inversion in the KTiOPO4 crystal by ion exchange; finally, periodically poled waveguide will be formed, which make the transmission light circumscribed within the domain inversion region. The main purposes of this project are first, to study the effect of ion implanted damage layer on ion exchange velocity, concentration and uniformity and to analyze the mechanism of ion implanted damage layer controlling the ion exchange; second, from the new domain nucleation and domain wall motion, to analyze lattice changes before and after the ferroelectric domain inversion in the ion exchange process and to explore the mechanism of ferroelectric domain inversion; third, to present the guide modes, near field intensity distribution, transmission loss and frequency doubling efficient of periodically poled waveguides. The results will give a new idea and data for fabrication of periodically poled waveguides, which are important for opening up the study of fabricating periodically poled waveguides.

周期极化KTiOPO4波导广泛应用于光参量振荡和放大、倍频与全光波长变换。离子交换法可以制备KTiOPO4波导并能实现铁电畴反转，但是铁电畴反转深度比波导深度小，即不能把光完全约束在畴反转区域。离子注入技术能够形成深度可控的晶格损伤层，可以有效地调控离子交换深度。本项目拟采用离子注入损伤层作为离子交换阻挡层，利用光刻掩膜和金属镀膜实现周期性图形，通过离子交换使得KTiOPO4晶体中铁电畴发生反转，制备周期极化波导，把传输光约束在畴反转区域。研究离子注入损伤层对离子交换的速度、浓度与均匀性的影响，分析离子注入对离子交换的调控机制；从新畴成核和畴壁运动出发，分析离子交换过程中铁电畴反转前后的晶格变化，探讨铁电畴反转机理；研究周期极化KTiOPO4波导的导模特性、近场光强分布、传输损耗与倍频效率等。研究结果对周期极化波导的制备提供新的思路与数据参考，对开拓周期极化波导的制备方法具有重要意义。

周期极化KTiOPO4波导广泛用于光参量振荡和放大、倍频与全光波长变换。离子交换法可以制备KTiOPO4波导并能实现铁电畴反转，但是铁电畴反转深度比波导深度小，即不能把光完全约束在畴反转区域。离子注入技术能够形成深度可控的晶格损伤层，可以有效地调控离子交换深度。本项目对KTiOPO4、MgGa2O4等晶体利用离子注入形成了光波导的基础上，研究了波导的导模特性、传输损耗和晶格膨胀。研究了离子注入KTiOPO4晶体对离子交换过程的调控作用。利用离子交换作为阻挡层，采用光刻掩膜和金属镀膜实现周期性图形，通过离子交换使得KTiOPO4晶体中铁电畴发生反转，制备了周期极化波导，实现了有效倍频转换。研究了周期极化KTiOPO4波导的导模特性、近场光强分布、传输损耗与倍频效率等。研究结果对周期极化波导的制备提供新的思路与数据参考，对开拓周期极化波导的制备方法具有重要意义。