AlGaAs-OI waveguides for nonlinear applications (Conference Presentation)
AlGaAs-OI waveguides for nonlinear applications (Conference Presentation)
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用于非线性应用的 AlGaAs-OI 波导（会议演示）
DOI：
10.1117/12.2289099
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
May S
中科院分区：
文献类型：
--
作者：
May S
砷化铝镓（AlGaAs）由于具有较强的二阶和三阶非线性系数，被认为是一种非常有前途的非线性光学材料。此外，通过改变铝的百分比，它的带隙可以很容易地增加到1.3 eV以上的值，这减轻了电信波长的两个光子吸收，这通常阻碍了硅基器件在这些应用中的使用。然而，GaAs/AlGaAs波导的主要缺点在于在垂直方向上相对较低的模态约束，这转化为高传播损耗。在硅包层上集成AlGaAs核心（即AlGaAs on Insulator或AlGaAs- oi）是一种非常有前途的非线性光子学材料平台，因为它结合了AlGaAs优越的非线性特性和硅包层的低折射率提供的非常强的模态约束。迄今为止，AlGaAs-OI最具挑战性的方面是平台本身的制造。在本次演讲中，将探讨用于非线性应用的AlGaAs-OI波导的设计，制造和测试的关键方面，重点是制造挑战以及如何克服它们。特别是，我们将回顾具有停止蚀刻层的AlGaAs脱膜设计，该设计允许有效去除GaAs衬底和干燥蚀刻化学物质，以获得光滑和垂直波导侧壁。我们还将讨论这些不同的设计和制造技术如何影响波导传播损耗和非线性应用的微环谐振器的性能。
Aluminium Gallium Arsenide (AlGaAs) is regarded as a very promising material for non-linear optical applications thanks to its strong second and third order non-linear coefficients. Moreover, its bandgap can be easily increased to values above 1.3 eV by varying the percentage of Aluminium, which mitigates the two photon absorption at telecom wavelengths that typically hinders the use of silicon based devices for these applications. However, the major drawback of GaAs/AlGaAs waveguides lies in the relatively low modal confinement in the vertical direction that translates into high propagation losses. The integration of an AlGaAs core on a silica cladding layer (i.e. AlGaAs on Insulator or AlGaAs-OI) is a very new and promising material platform for non-linear photonics as it combines the superior non-linear properties of AlGaAs with the very strong modal confinement offered by the low refractive index of the silica cladding. To date the most challenging aspect of AlGaAs-OI has been in the fabrication of the platform itself. In this talk key aspects regarding the design, fabrication and testing of AlGaAs-OI waveguides for nonlinear applications shall be explored, focussing on the fabrication challenges and how they were overcome. In particular, we will review AlGaAs epilayer designs with stop-etch layers that allow effective removal of the GaAs substrate and dry etching chemistries for smooth and vertical waveguide sidewalls. We will also discuss how these different designs and fabrication techniques impact on the waveguide propagation losses and on the performance of micro-ring resonators for non-linear applications.