Towards Ubiquitous GRAphene based RF COmmunications - demonstrating and understanding graphene based plasmonic THz antenna potential and limitations

纳米技术正在日益提供大量的新工具来设计和制造小型化设备，如无处不在的传感器，可穿戴电子产品或普及计算系统。这些设备需要无线通信来进行信息共享和协调。不幸的是，减小这种设备的尺寸（以及伴随的成本）受到金属天线的尺寸的严重限制。石墨烯由于其特殊的色散关系和支持表面等离子体激元（SPP）的能力，提供了一个激进的替代品，以缩小天线的数量级。实际上，预测具有几微米的横向尺寸的石墨烯RF等离子体微天线在太赫兹频带（0.3- 10 THz）中以低达两个数量级的频率谐振，并且相对于金属对应物具有更高的辐射效率。因此，石墨烯微天线为未来的小型化无线系统提供了巨大的集成潜力，并代表了未来主导ICT应用的使能技术，例如物联网。在这个项目中，我们将：i）提出一个实验原型演示，展示和评估石墨的实际操作。在这里，基于太赫兹石墨烯的光电导发射器将被证明具有0.2和3太赫兹之间的操作频率。设想天线长度的目标减少至少10倍。该分析包括该概念向较低μ波频率的可扩展性。ii）将开发在现实技术可实现的参数下石墨烯的潜在和限制性能因素的详细定量评估。iii）将实现对这些限制的微观起源的基本理解，以便在此（和其他THz）应用的背景下指导石墨烯材料优化。

Nanotechnology is increasingly providing a plethora of new tools to design and manufacture miniaturized devices such as ubiquitous sensors, wearable electronics or pervasive computing systems. Such devices require wireless communications for information sharing and coordination. Unfortunately, reducing the size (and concomitantly cost) of such devices is severely restricted by the dimensions of metallic antennas. Graphene offers a radical alternative to downscale antennas by orders of magnitude thanks to its special dispersion relation and its ability to support surface-plasmon polaritons (SPP). Indeed, a graphene RF plasmonic micro-antenna with lateral dimensions of a few micrometers is predicted to resonate in the terahertz band (0.3-10THz) at a frequency up to two orders of magnitude lower and with a higher radiation efficiency with respect to metallic counterparts. In consequence, graphene micro-antennas provide a huge integration potential for future miniaturized wireless systems and represents an enabling technology for the future dominant ICT applications envisioned by e.g. Internet of Things. In this project we will: i) present an experimental prototype demonstration, which shows and assesses the practical operation of a graphenna. Here, photoconductive emitters based on THz graphennas will be demonstrated with operation frequencies between 0.2 and 3 THz. A target reduction of antenna length by at least a factor of 10 is envisaged. The analysis includes scalability of the concept towards lower µ-wave frequencies. ii) A detailed quantitative evaluation of the potential and limiting performance factors of graphennas under realistic technologically achievable parameters will be developed. iii) A fundamental understanding of the microscopic origin of these limitations will be achieved, in order to guide graphene material optimization in the context of this (and other THz) applications.