EAGER: SAPPHIRE BASED INTEGRATED MICROWAVE PHOTONICS

微波光子学是指利用光作为载体对高频电信号进行处理的领域。它在国防和民用方面都取得了巨大的成功。 微波光子学的未来应用要求其性能有显著的提高，同时，电子器件应该具有更有利的特性，例如小尺寸、轻重量和低功耗。 该项目提出开发一种新的“集成微波光子芯片”，该芯片可以在单个芯片上集成微波光子元件的多种功能，并以非常低的成本提供减小的尺寸、重量和功率。如果成功，这项技术将在雷达等国防系统以及手机、传感器和卫星通信等许多民用领域得到广泛应用。 拟议的研究活动为研究生在集成光子学领域提供全面的培训;半导体器件设计，模拟，制造和表征;以及科学数据和结果的准备，分析，解释和传播。 该项目将用于招募本科荣誉学生谁可以使用本研究的某些方面为他们的论文。一个强大的互动计划，与当地的历史上黑人学院和大学/少数民族机构已经形成，以激励代表性不足的少数民族学生参加research.Integrated微波光子（IMWP）集成微波光子组件/子系统的功能，在单片或混合光子芯片，它提供了减少的尺寸，重量和功率在一个非常低的成本。该项目提出利用R面蓝宝石作为一种变革性的、高性能的和自一致的IMWP平台，为实现完全集成的MWP系统提供了一种可行的方法。所提出的方法能够将整套微波和光学元件（例如光源、模拟和数字信号处理电路、光探测器、控制电路和蓝宝石上硅（SOS）射频（RF）电路）集成到一体化蓝宝石平台上，以实现高性能和低成本的混合信号光链路。蓝宝石具有较低的折射率，与Si 3 N4的折射率差为0.3。因此，它可以利用成熟的Si 3 N4低损耗波导技术，通过用蓝宝石晶片替代石英晶片来生产类似的低损耗波导基无源元件。对于RF应用，由于低损耗光波导，蓝宝石平台具有获得高得多的动态范围的潜力，而与芯片外1.55微米激光器相结合的竞争性Si光子平台遭受强双光子吸收，因此具有有限的动态范围。 作为透明衬底，蓝宝石将实现通用的3D光子/电子集成架构。该项目的目的是，首先通过查明和调查关键的“根本挑战”来研究拟议办法的“可行性”，然后进行一项概念验证研究，为克服所查明的障碍提供一条有效的途径，最后就拟议研究是否可行提出结论性建议。作为一个完全集成的解决方案，从根本上解决IMWP中最重要的技术挑战，如果成功，新平台将在国防系统中找到巨大的应用，如雷达信号处理和许多民用应用。宽波长覆盖范围使片上传感应用成为可能。 它有可能取代目前的硅光子学，用于太空和核应用等恶劣环境。

Microwave photonics refers to a field that utilizes light as carrier to process high frequency electrical signals. It has shown great success in both defense and civilian applications. The future applications of microwave photonics demand a dramatic improve in performance while, in the same time, electronic devices should have more favorable features such as small size, lightweight, and low-power consumption. This project proposes to develop a new "Integrated Microwave Photonics chip" which could potentially integrate several functions of microwave photonic components on a single chip and also offer reduced size-weight-and-power at a very low cost. If successful, the developed technology would find tremendous applications in defense systems, such as Radar, and many civilian applications, such as cell phones, sensing, and datacom. The proposed research activities provide comprehensive training for graduate students in the areas of integrated photonics; semiconductor device design, simulation, fabrication, and characterization; as well as in preparation, analysis, interpretation, and dissemination of scientific data and results. The project will be used to recruit undergraduate honor students who may use certain aspects of this research for their thesis. A strong interaction plan with a local Historically Black Colleges and Universities/Minority Institution has been formed to inspire underrepresented minority students to participate research.Integrated Microwave Photonics (IMWP) incorporates the functions of microwave-photonic components/subsystems in a monolithic or hybrid photonic chip, which offers reduced size-weight-and-power at a very low cost. This project proposes to utilize R-plane sapphire as a transformative, high-performance and self-consistent IMWP platform which provides a feasible approach for realizing fully-integrated MWP systems. The proposed approach enables the integration of complete sets of microwave and optical components such as light sources, analog and digital signal processing circuits, light detectors, control circuits, and Silicon on Sapphire (SOS) radio-frequency (RF) circuits all-in-one sapphire platform to achieve high-performance and low-cost mixed-signal optical links. Sapphire has a lower refractive index with an index difference of 0.3 with Si3N4. Therefore, it could leverage the mature Si3N4 low-loss waveguide technology to produce similar low-loss waveguide-based passive components by drop-in replacing quartz wafers with sapphire wafers. For RF applications, the sapphire platform has a potential to obtain much higher dynamic range due to low-loss optical waveguides while the competing Si-photonics platform combined with off-chip 1.55 micron laser suffers from the strong two-photon absorption and therefore has a limited dynamic range. As a transparent substrate, sapphire would enable a versatile 3-D photonics/electronics integration architecture. This project aims to, first, study the "feasibility" of the proposed approach by identifying and investigating key "fundamental challenges", then, conduct a proof-of-concept study to provide an effective route for overcoming the identified obstacles, and, eventually, provide a conclusive recommendation as to whether the proposed research is feasible. As a fully integrated solution to fundamentally address the most important technical challenge in IMWP, if successful, the new platform would find tremendous applications in defense systems, such as Radar signal processing, and many civilian applications. The broad wavelength coverage enables on-chip sensing applications. It could potentially replace the current Si-photonics for datacom and be used in harsh environments such as space and nuclear applications.