OP: Hybrid Silicon-Vanadium Dioxide Resonators for Tbps Optical Communication

摘要非技术：单纯通过增加晶体管来提高计算处理速度越来越困难，因为特征尺寸接近原子尺寸，小体积下功耗和散热存在问题，片上通信的瓶颈减慢了数据传输。其中最有希望显著提高处理速度的途径是使用光脉冲传输数字数据。如果计算机要在硅芯片上利用光实现太赫兹级处理，那么高速、低功耗的光调制器就必不可少。然而，由于其固有的物理性质，全硅光调制器无法实现如此高速的信号调制。在这个项目中，研究了硅芯片上的硅-二氧化钒混合光调制器对光的太赫兹速度调制。该项目还将发展对开关机制的超快行为和固有材料特性的基本见解-二氧化钒的绝缘体到金属的转变。参与的学生将在纳米技术、物理、工程和材料科学的交叉领域进行前沿研究。教师和研究生将通过参加范德比尔特大学已经建立的成功的推广项目，与纳什维尔地铁和周围田纳西州农村县的初高中学生分享他们对科学、技术、工程和数学的热情。技术：高速、低功率的光调制器对于硅光子学的未来是至关重要的，是超高速通信的解决方案。该项目的目标是通过利用二氧化钒的超快绝缘体到金属的转变，在混合硅：二氧化钒光子器件中以100 fJ/开关的支出达到至少500 GHz的开关速度。混合装置还将用于探测二氧化钒中光学诱导绝缘体到金属动力学的强电子相关性。本研究的具体目标是：(1)制备二氧化硅杂化光子元件，比较二氧化钒中光电诱导相变和光电诱导相变的切换速度；(2)通过最先进的模拟测试器件性能，了解二氧化钒的相变如何控制器件中光脉冲的模式结构；(3)通过干涉法监测Mach-Zehnder几何中光脉冲的相位和振幅，测量电信波段中二氧化钒的时变介电函数。该项目的核心知识价值在于其理解和利用二氧化钒在1500纳米附近的超快相变动力学的雄心。技术上的挑战是在具有微米尺度足迹的混合硅：二氧化钒结构中展示500 GHz的切换速度，使用电信频段的超快激光来启动二氧化钒的相变。这将需要仔细的光学工程，以确保激光泵浦和混合相变结构之间的低注入损失。证明光诱导的VO2超快相变可以在一个实用的、硅器件兼容的架构和处理机制中得到利用，将是迈向片上太赫兹级处理的一个转型步骤。该项目本质上是跨学科的，培养学生在光学科学与工程、硅光子学、材料科学和先进的计算技术。项目参与者将在纳什维尔市公立学校和田纳西州中部农村地区的初高中学生中开展成熟的科学和技术推广项目。

Abstract TitleHybrid Silicon-Vanadium Dioxide Modulators for Record High Speed Optical CommunicationAbstractNontechnical:It is increasingly difficult to raise computational processing speed simply by adding more transistors because feature sizes are approaching atomic dimensions, power and heat dissipation are problematic in small volumes, and bottlenecks in on-chip communication slow down data transfer. Among the most promising routes to significantly faster processing speeds is using light pulses to carry digital data. High-speed, low-power optical modulators that can encode signals in light are essential if computers are to achieve THz-scale processing using light on silicon chips. However, due to their intrinsic physical properties, all-silicon optical modulators cannot achieve signal modulation at such a high speed. In this project, hybrid silicon-vanadium dioxide optical modulators on a silicon chip are investigated for THz-speed modulation of light. Fundamental insights on the ultrafast behavior and intrinsic materials properties of the switching mechanism - the insulator-to-metal transition in vanadium dioxide - will also be developed in the project. Participating students will do cutting-edge research at the intersection of nanotechnology, physics, engineering, and materials science. Faculty and graduate students will share their enthusiasm for science, technology, engineering, and mathematics with middle and high school students in Metro Nashville and surrounding rural Tennessee counties by participating in successful outreach programs already established at Vanderbilt.Technical:High-speed, low-power optical modulators are essential to the future of silicon photonics as the solution to ultrafast communication. The goal of this project is to reach switching speeds of at least 500 GHz with an expenditure of 100 fJ/switch in hybrid silicon:vanadium dioxide photonics devices by exploiting the ultrafast insulator-to-metal transition of vanadium dioxide. The hybrid devices will also be used to probe the strong electron correlations that underlie the optically induced insulator-to-metal dynamics in vanadium dioxide. The specific objectives of the research are to: (1) fabricate hybrid silicon:vanadium dioxide photonic components and compare the switching speed of the optically and electro-optically induced phase transition in vanadium dioxide; (2) benchmark device performance against state-of-the-art simulations to learn how the phase change in vanadium dioxide controls the mode structure of optical pulses in the devices; and (3) measure the time-dependent dielectric function of vanadium dioxide in the telecommunications band by interferometric monitoring of the phase and amplitudes of optical pulses in Mach-Zehnder geometries. The intellectual merit at the heart of the project lies in its ambition to understand and exploit the ultrafast dynamics of the phase transition of vanadium dioxide near 1500 nm. The technological challenge is to demonstrate 500 GHz switching speeds in hybrid silicon:vanadium dioxide structures with micron-scale footprints using ultrafast lasers in the telecom band to initiate the phase transition of vanadium dioxide. This will require careful optical engineering to ensure low injection loss between the laser pump and the hybrid phase-changing structure. Demonstrating that the optically induced, ultrafast phase transition in VO2 can be harnessed in a practical, silicon-device-compatible architecture and processing regime would be a transformational step toward on-chip THz-scale processing. The project is inherently interdisciplinary, training students in optical science and engineering, silicon photonics, materials science, and advanced computational techniques. Project participants will engage in well-established science and technology outreach programs targeting middle and high school students in both Nashville city public schools and rural counties in middle Tennessee.