CAREER: Van der Waals material integrated ultra-low power nanophotonics

非技术描述：信息处理和通信是许多使现代生活成为可能的技术的核心。这些技术在过去几十年里经历了指数级的增长，这要归功于电子设备的积极扩展。然而，下一代信息技术不能仅靠扩展晶体管来支持，它将严重依赖数据中心和云计算来推动性能改进。随着大型科技公司在这些领域的投资增加，我们已经经历了这一趋势。为了支持这一架构，我们需要将作为现代互联网主干的光互连技术(即光纤)扩展到更短的规模。超越了经典的计算和通信技术，量子力学为实现信息技术的范式转变提供了机会。然而，所有这些技术都需要超低功率的光电设备；电力需求几乎比现有设备低四个数量级。在我的研究中，我的目标是使用集成了氮化硅光子电路的原子薄材料来制造这些设备。具体地说，我们的目标是开发一种光调制器和光开关，可以用最小的功率改变光的传输。这些器件将使用先进的半导体制造技术制造。在开发新技术的同时，该提案旨在将设计-建造-测试模块纳入现有的以授课为基础的纳米光子学课程中，为集成光子学领域的下一代知识工作者提供实践经验。技术描述：超低功率可调和非线性光学器件是许多光学技术的关键，包括光电信息处理、通信和强关联材料的光子量子模拟。目前，调制通过光子器件的光传输或观察非线性输入输出响应所需的功率太高。这种功率可以通过在较长时间内将电子和光子波函数空间限制在纳米尺度上来降低。与新兴低维材料集成的纳米光子谐振器为制造超低功率光电子器件提供了一个有吸引力的平台。为此，该提议旨在将范德华(VDW)材料(例如，石墨烯或过渡金属二卤化物)及其异质结构与氮化硅纳米谐振器相结合。选择氮化硅是因为它的禁带宽度大，与大规模半导体制造兼容。VDW材料之所以被选中，是因为它们独特的量子性质、大的激子结合能和原子厚度，使其具有极小的活性体积和前所未有的材料兼容性；它们可以转移到任何衬底上，而不需要显式的晶格匹配。将数值模拟、器件制作和光学表征相结合，将追求三个研究目标：(I)建立VDW材料的实验驱动模型--腔耦合；(Ii)在耦合腔阵列中展示几个光子水平的光学非线性；(Iii)创建每个开关具有阿焦耳电能的电光调制器。虽然这些设备的最初应用将是在超低功率经典光学信息科学中，但同一平台可以用于开发量子技术，包括量子多体模拟和量子信号换能器。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。

Non-Technical Description: Information processing and communication are at the heart of many technologies that enable modern life. These technologies have experienced exponential growth over the past several decades, thanks to the aggressive scaling of electronic devices. Next-generation information technologies, however, cannot be supported by only scaling transistors, and will rely heavily on data centers and cloud computing to drive performance improvements. We are already experiencing this trend with the increased investment from large technology companies in these sectors. To support this architecture, we need to bring optical interconnect technology (i.e., fiber optics), which is the backbone of the modern internet, to shorter length scales. Going beyond classical computing and communication technologies, quantum mechanics presents an opportunity to realize a paradigm shift in information technology. All these technologies, however, require ultra-low power optoelectronic devices; the power requirement is almost four orders of magnitude lower than that of existing devices. In my research, I aim to create these devices using atomically thin materials integrated with silicon nitride photonic circuits. Specifically, we aim to develop an optical modulator and optical switch, that can change light transmission using minimal power. These devices will be fabricated using well-developed semiconductor manufacturing technology. Along with developing new technology, the proposal aims to incorporate a design-build-test module in existing lecture-based nanophotonics courses to provide hands-on experience to the next-generation knowledge workers in the field of integrated photonics.Technical Description: Ultra-low-power tunable and nonlinear optical devices hold the key for numerous optical technologies including optoelectronic information processing, communication, and photonic quantum simulations of strongly correlated materials. Currently, the power required to modulate the light transmission through photonic devices or to observe a nonlinear input-output response is too high. This power can be reduced by spatially confining the electronic and photonic wave functions to a nanometer-length scale for an extended period of time. Nanophotonic resonators integrated with emerging low-dimensional materials present an attractive platform to create ultra-low-power optoelectronic devices. To that end, this proposal aims to integrate van der Waals (vdW) materials (e.g., graphene or transition metal dichalcogenides) and their heterostructures with silicon nitride nano-resonators. The choice of silicon nitride is motivated by its large bandgap and compatibility with large-scale semiconductor manufacturing. The vdW materials are chosen for their unique quantum properties, large exciton binding energies, and atomic thinness that enable extremely small active volumes and unprecedented material compatibility; they can be transferred onto any substrate without requiring explicit lattice matching. Combining numerical simulation, device fabrication, and optical characterization, three research aims will be pursued: (i) develop an experiment-driven model for vdW material?cavity coupling; (ii) demonstrate optical nonlinearity at the few photon level in a coupled cavity array, and (iii) create an electro-optic modulator with attojoule electrical energy per switching. While the initial applications of these devices will be in ultra-low-power classical optical information science, the same platform can be used for developing quantum technologies, including quantum many-body simulations and quantum signal transduction.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.