Collaborative Research: Tellurene mid-infrared integrated photonics

缺乏与普通半导体衬底兼容的光学材料是中红外领域集成光子器件发展的一个长期障碍。该奖项支持一个合作团队进行基础研究，以促进新兴光学纳米材料与中红外光子学平台的集成知识。这项研究旨在实现基于新型光学纳米材料--二维碲烯的中红外光子元件和电路的设计、制造和集成。碲是一种原子薄的元素碲晶体，是一种新兴的可伸缩合成的二维材料，它独特地结合了窄且可调的带隙能量、高载流子迁移率、极大的电光活性和优异的化学稳定性，使其成为中红外光子学的一种有前途的多功能材料平台。中红外波段(2-20微米)对于热成像、光谱传感、红外对抗和自由空间通信具有重要的技术意义。拟议的基于碲的设备平台一旦得到演示，将对中红外集成光子学产生变革性的影响。据预测，设想中的探测器和调制器设备的性能都将远远超过最先进的水平。这项研究涉及多个学科，包括材料科学、电气工程、光子学、器件物理、制造和化学。多学科研究和拟议的外展活动将为学生提供宝贵的机会，让他们接触尖端纳米技术和光学科学，以激发他们对STEM职业道路的兴趣。2-D材料由于其独特的光学性质而成为一种很有前途的光子集成材料类别，这是传统块状和薄膜材料所不具备的。然而，要充分发挥二维材料在中红外集成光子学中的应用潜力，还需要克服一些科学和技术障碍。本研究旨在填补溶液合成碲与中红外光子学平台集成的知识空白。其目的是(1)展示基于碲的高性能波导集成室温中红外光电探测器和超快电光调制器，以及(2)探索溶液合成碲作为集成中红外光子器件的新型光学材料的独特优势和能力。研究小组将创新一种处理方案，使用成分设计的硫化物玻璃作为导光介质和红外透明栅电介质，在碲上直接制造波导结构。这种单片方法利用了硫化物玻璃的宽带中红外透明性和近室温工艺，不仅简化了集成过程，还允许专门优化光子电路，并以光刻精度精确对准碲晶体。该团队还将开发一个基于物理的框架来设计和指导材料合成、器件制造和系统集成。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。

Lack of optical materials compatible with common semiconductor substrates presents a standing hurdle for integrated photonic device development in the mid-IR domain. This award supports a collaborative team to conduct fundamental research to advance knowledge for the integration of emerging optical nanomaterials with the mid-IR photonics platform. The research aims to enable the design, fabrication, and integration of mid-IR photonic components and circuits based on a new optical nanomaterial, namely two-dimensional (2-D) tellurene. Tellurene, atomically thin crystals of elemental tellurium, is an emerging 2-D material amenable to scalable synthesis and uniquely combines small and tunable bandgap energies, high carrier mobility, exceptionally large electro-optic activity, and superior chemical stability, which makes it a promising and versatile material platform for mid-IR photonics. The mid-IR spectral band (2-20 micro-meter) is of significant technological importance for thermal imaging, spectroscopic sensing, infrared countermeasures, and free-space communications. The proposed tellurene-based device platform, once demonstrated, will have a transformative impact on mid-IR integrated photonics. The envisioned detector and modulator devices both are predicted to have performances far exceeding the state-of-the-art. This research involves several disciplines, including materials science, electrical engineering, photonics, device physics, manufacturing, and chemistry. The multi-disciplinary research combined with the proposed outreach activities will provide valuable opportunities for exposing the students to cutting-edge nanotechnology and optical sciences to inspire their interest in STEM career paths.2-D materials have emerged as a promising material group for photonic integration, given their singular optical properties not found in conventional bulk and thin-film materials. However, some scientific and technical barriers are yet to be overcome to realize the full application potential of 2-D materials for mid-IR integrated photonics. This research is to fill the knowledge gap on the integration of solution-synthesized tellurene with the mid-IR photonics platform. The objectives are (1) to demonstrate high-performance waveguide integrated room-temperature mid-IR photodetectors and ultrafast electro-optic modulators based on tellurene, and (2) to explore the unique advantage and capability of solution-synthesized tellurene as a novel optical material for integrated mid-IR photonic devices. The research team will innovate a processing scheme that directly fabricates waveguide structures on tellurene using compositionally-engineered chalcogenide glass as both the light guiding medium and an infrared-transparent gate dielectric. This monolithic approach capitalizes on the broadband mid-IR transparency and near-room-temperature processing of chalcogenide glass to not only simplify the integration process but also allow the photonic circuit to be specifically optimized and precisely aligned to tellurene crystals with lithographic accuracy. The team will also develop a physics-based framework to design and guide the material synthesis, device fabrication, and system integration.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.