基于飞秒激光直写途径的微腔光子芯片研究
文献类型：学位论文
| 作者 | 方致伟 |
| 文献子类 | 博士 |
| 导师 | 程亚 |
| 关键词 | 飞秒激光 Femtosecond laser 微腔光子芯片 microresonator-based photonic chip 熔石英微环芯腔 fused silca microriod 铌酸锂微盘腔 Lithium niobate microdisk 铌酸锂双盘腔 Lithium niobate double-disk microresonators |
| 其他题名 | Investigations on the microresonator-based photonic chips fabricated with femtosecond laser direct writing |
| 英文摘要 | 回音壁模式光学微腔通过光在腔壁内表面发生持续全内反射把光长时间约束在一个微小的空间体积内，由此可在腔内产生极强的电场，有效地增强光与物质之间的相互作用。近几十年来，回音壁模式光学微腔逐渐成为研究热点，已在光信息处理、光学传感、非线性光学、腔量子电动力学和腔光机械力学等领域都得到了广泛应用。但是目前大部分的应用都是依赖于独立的高Q值回音壁模式光学微腔与外界的三棱镜、光纤锥和波导等进行近场耦合，需要使用精密的三维位移平台精确控制微腔与耦合器件的间隔，此类耦合系统受环境影响非常大很不稳定。因此科研人员开始致力于制备出微腔与波导等其他功能性元件集成的微腔光子芯片，使整个微腔耦合系统更加稳固更加微型化。 早期的回音壁模式光学微腔是通过高温熔融的方法制备的微球腔，此工艺非常简单且能容易制得超高品质因子的微腔。但是高温熔融不能精确控制微腔尺寸且制得的微球腔不易集成。随着半导体行业的发展，光刻工艺也应用到制备回音壁模式光学微腔上，在同一芯片上可同时制备出大规模的高品质因子和小模式体积的微盘腔、微环芯腔和微环腔，且能实现微盘腔、微环腔与波导等功能性元器件集成。但是光刻工艺只能在一些半导体材料上制备出平面结构。 飞秒激光微加工技术不仅加工精度高而且能够对任何透明材料进行任意三维加工，在微纳光子学、微机电系统和微流控芯片等领域都得到重要应用。我们课题组已经实现利用飞秒激光微加工技术在石英衬底上制备出微腔与微流通道集成的生物传感器。相对于传统的微腔制备工艺，飞秒激光直写技术可以制备任意的三维分布的光学微腔，可以灵活地对任何透明材料进行加工。 本论文的主要工作是利用飞秒激光直写技术制备出微腔与光纤锥、波导集成的微腔光子芯片，具体分为以下三个方面： 1． 利用飞秒激光三维微加工技术制备出高品质熔石英微环芯腔，并通过使用二氧化碳激光焊接技术将光纤锥稳固集成在与微腔的最佳耦合位置上，集成后的微腔Q值高达2.12×106。 2． 利用飞秒激光快速直写与聚焦离子束精细研磨技术在铌酸锂单晶薄膜上制备出铌酸锂微盘腔与波导的集成器件，集成后的铌酸锂微盘腔Q值高达1.67×105。 3． 利用飞秒激光快速直写结合聚焦离子束精刻技术在双层铌酸锂单晶薄膜上制备出垂直耦合的铌酸锂双盘腔，光学品质因子达1.35×105。; Whispering-gallery-mode (WGM) microresonators offer the capability to trap photons in a small volume by total internal reflection for a long duration. The long photon lifetimes lead to the generation of strong electric fields, which in turn effectively enhance the interaction between light and matter. During the past several decades, researches on WGM microresonators have been contiuosly prospering worldwide to enable applications ranging from optical signal processing, optical sensing, and nonlinear optics to quantum electrodynamics and cavity-optomechanics. However, many of their applications rely on the use of individual WGM microresonators, and the light beam has to be coupled into and out from the microresonator using external prism, tapered fiber or waveguide. Stable 3D optical stages are required to achieve high presicion positioning of the coupling components. Therefore, it would be desirable to fabiricate microrsonator-based photonic chips which monolithically integrate microresonators with waveguides, thereby the integrated coupling system can be miniaturized and will be more stable against the disturbance from the environment. Previously, fabrication of the microsphere resonators has been achieved using high temperature melting, which has enabled fabrication of ultrahigh Q resonators. However, the melting process cannot allow to accurately control the diameter of microresonators, and the fabricated microspheres cannot be easily integrated into a system. Owing to the development of semiconductor manufacturing technology, lithographic techniques are applied to the fabrication of on-chip microdisk, microtoroid, and microring resonators, which have high Q factors and small volumes. This approach provides a means for integration of the coupling waveguides with the microdisks or microrings. Nevertheless, this method can mainly be used to fabricate planar structures on semiconductor materials. Femtosecond laser micromachining has been a promising technique for fabricating three-dimensional (3D) micro/nano-structures in transparent materials with ultrahigh precision, which provides the potential for applications in micro/nano optics, microelectromechanical systems (MEMS), and microfluidics. We have achieved fabrication of a high-Q factor microtoroid resonator integrated in a microfluidic channel. Compared with the conventional planar lithographic fabrication methods, femtosecond laser micromachining has the unique capability to fabricate three-dimensional (3D) micro/nano-structures in various transparent materials. In this thesis, we focus on the monolithic integration of microresonators-tapered fiber/waveguide systems based on femtosecond laser micromachining. The main results are as follows: 1. We demonstrated fabrication of a fused silica microresonator using femtosecond laser three-dimensional micromachining. A fiber taper is reliably assembled to the microtoroid using CO2 laser welding. Specifically, we achieved a high-Q factor of 2.12×106 in the microresonator-fiber assembly by optimizing the contact position between the fiber taper and the microtoroid. 2. We demonstrated integrating a high quality factor lithium niobate microdisk resonator with a free-standing membrane waveguide by femtosecond laser direct writing followed by focused ion beam milling. The Q-factor of the microresonator was measured as high as 1.67×105. 3. We demonstrated fabrication of a high quality factor lithium niobate double-disk WGM microresonator using femtosecond laser assisted ion beam milling. The Q-factor of LN double-disk was measured as high as 1.35×105. |
| 学科主题 | 光学 |
| 源URL | [http://ir.siom.ac.cn/handle/181231/31111]  |
| 专题 | 中国科学院上海光学精密机械研究所 |
| 作者单位 | 中国科学院上海光学精密机械研究所 |
| 推荐引用方式 GB/T 7714 | 方致伟. 基于飞秒激光直写途径的微腔光子芯片研究[D]. |
入库方式： OAI收割
来源：上海光学精密机械研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。