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

纳米技术正在越来越多地提供大量新工具来设计和制造微型化设备，如无处不在的传感器、可穿戴电子设备或普适计算系统。这类设备需要无线通信来实现信息共享和协调。不幸的是，金属天线的尺寸严重限制了这种设备的尺寸(以及随之而来的成本)。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，提供了一种以数量级取代小规模天线的激进选择。事实上，据预测，横向尺寸为几微米的石墨烯射频等离子体微天线将在太赫兹频段(0.3-10THz)内共振，频率最高可低两个数量级，辐射效率高于金属天线。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，并为物联网等未来主导的ICT应用提供了一种使能技术。在这个项目中，我们将：i)展示一个实验原型演示，它展示和评估了石墨纳的实际操作。在这里，将演示基于太赫兹石墨层的光导发射器，其工作频率在0.2到3太赫兹之间。预计目标天线长度将减少至少10倍。该分析包括将该概念扩展到更低的µ波频率。二)将在现实的技术上可实现的参数下，对石墨层的潜在和限制性能因素进行详细的定量评估。Iii)将从根本上理解这些限制的微观来源，以便在此(和其他太赫兹)应用的背景下指导石墨烯材料的优化。

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.