Reconfigurable free-form metamaterials: a new design paradigm for integrated optoelectronics based on 2D materials

非技术：硅光电子是一个快速增长的行业，未来十年可能会达到每年超过10亿美元的价值。与此同时，光子集成电路的复杂性增加了一个数量级以上。然而，硅在用于电信的波长上的光学响应相对较弱。因此，当前的光电子技术依赖于集成具有所需特性的其他材料。在这种背景下，石墨烯已经成为实现硅兼容光电子器件的极佳候选者。石墨烯是一种原子厚度的二维材料，由碳制成。它的强度几乎是钢的100倍，有效地传导热量和电力，并具有不同寻常的光学特性。最近的实验报告已经接近了基于石墨烯的设备的预测性能极限。目前还不清楚如何在减小设备尺寸的同时进一步提高设备性能。因此，基于石墨烯的光电子器件需要新的范例。该项目将为实现集成光电子器件开辟一条新的途径。纳米制造将用于将石墨烯集成到有源器件中，并设计出具有纳米级分辨率的有效光学性质。这些设备将与CMOS技术完全兼容，并承诺大幅减少设备占地面积和损耗，同时提供高速度和低能耗。该项目通过NSF-US/爱尔兰研发伙伴关系，汇集了来自美国、北爱尔兰和爱尔兰共和国的多学科研究人员团队。作为该项目的一部分，国际合作将为国际学生交换和研究合作提供难得的机会。技术：拟议的工作旨在开发一种新的基于石墨烯的与CMOS兼容的光电子学家族。提出的方法背后的两个前提是：(I)通过纳米制造，有可能在深亚波长维度上对器件的局部折射率进行空间设计；以及(Ii)通过集成二维材料层，有可能在更小的面积内提供有源功能。这些器件的工作依赖于多个共振纳米光子模式之间的耦合，这不仅使它们对制造误差具有健壮性，而且能够在减少占地面积的情况下实现较宽的光学带宽。确定了三个主要研究方向：(A)开发高性能超紧凑型石墨烯电光调制器。(B)将拟议的设计概念扩展到调制器以外的其他光电子器件(例如移相器、有源耦合器、偏振器和传感器)。(C)在一块光学芯片上单片集成多个器件，并使用适当的cmos电路驱动。这项拟议的研究具有高度的变革性，因为它结合了两个新兴的研究概念，以克服当前集成光电子技术的主要限制。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical:Silicon photonics is a rapidly growing industry, potentially reaching an annual value of over a billion dollars in the coming decade. In parallel, the complexity of photonic integrated circuits has increased by more than an order of magnitude. The optical response of silicon at wavelengths used for telecommunications, however, is relatively weak. Current optoelectronic technologies therefore rely on integrating other materials with the desired properties. In this context, graphene has emerged as an excellent candidate to realize silicon-compatible optoelectronic devices. Graphene is an atom-thick, two-dimensional material made from carbon. It is nearly 100 times stronger than steel, conducts heat and electricity efficiently, and has unusual optical properties. Recent experimental reports have already approached the predicted performance limits of graphene-based devices. It is not obvious how the device performance can be further enhanced while simultaneously reducing device size. Thus, new paradigms in graphene-based optoelectronic devices are required. This project will develop a new approach for realizing integrated optoelectronic devices. Nanofabrication will be used to integrate graphene into active devices and engineer the effective optical properties with nm scale resolution. These devices will be fully compatible with CMOS technology and promise dramatic reductions in device footprint and losses, while providing fast-speed with low energy consumption. The project brings together a multidisciplinary team of researchers from the United States, Northern Ireland, and the Republic of Ireland through the NSF-US/Ireland R&D Partnership. International cooperation will provide exceptional opportunities for international student exchange and research collaboration as part of this project.Technical:The proposed work aims to develop a new family of graphene-based CMOS-compatible optoelectronics. The two premises behind the proposed approach are that: (i) via nanofabrication, it is possible to spatially engineer the local refractive index of the device at deep sub-wavelength dimensions; and, (ii) by integrating two-dimensional material layers, it is possible to provide active functionality in a reduced area. The operation of these devices relies on the coupling between a number of resonant nano-photonic modes, which does not only make them robust to fabrication errors but also enables broad optical bandwidth in a reduced footprint. Three main research thrusts are identified: (a) development of high-performance ultra-compact graphene electro-optic modulators. (b) Extension of the proposed design concept to other optoelectronic devices beyond modulators (e.g., phase shifters, active couplers, polarizers, and sensors). (c) Monolithically integrate multiple devices on an optical chip and drive with proper CMOS circuitry. The proposed research is highly transformative since it combines two emerging research concepts so to overcome the main limitations of current integrated optoelectronic technologies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.