Nanoscale quantum dot photodetectors with high integratability for nanophotonic integrated circuits

目的：本项目旨在为纳米光子集成电路提供具有高灵敏度和高带宽的新型纳米级光电探测器。该方法利用纳米晶体量子点在纳米间隙电极中的自组装或溶液工艺，实现了与各种纳米光子元件的高制造集成性。为了提高灵敏度和带宽，探索了等离子体效应的结合和新的制造工艺来减少隧道障碍。知识价值：这项研究将展示纳米级量子点光电探测器的新设计和制造，可以很容易地集成到纳米光子器件中。该器件结构利用集中的强电场来提高效率和电荷输运。优化量子点沉积的化学和条件的研究将为提高量子点器件的速度提供一条途径，这是量子点器件面临的主要挑战。利用等离子体聚焦光场和提高量子效率将有助于解决纳米光子学中普遍存在的光耦合问题。如果成功，该研究将为完全集成的纳米光子光探测提供第一个解决方案。更广泛的影响：纳米光子学领域的发展增加了对更快、更小、更敏感的片上光电检测的需求。考虑到纳米光子学在材料和制造工艺上的差异，一种具有完全制造集成性的纳米级光电探测器尚未得到证实。这项研究的成功将对纳米光子集成电路以及更广泛的光学计算、通信和传感领域产生变革性的影响。这项研究也将为研究生和本科生提供令人兴奋的多学科培训机会，并通过多元化发展，教育和外展活动对社会产生更广泛的影响。

Objective: The objective of this program is to demonstrate new nanoscale photodetectors with high sensitivity and bandwidth for nanophotonic integrated circuits. The approach exploits self-assembly or solution-process of nanocrystal quantum dots in nanogap electrodes to achieve high fabrication integratability with varieties of nanophotonic components. Incorporation of plasmonic effects and new fabrication processes to reduce tunneling barriers are explored to enhance sensitivity and bandwidth.Intellectual merit: This research will demonstrate new design and fabrication of nanoscale quantum dot photodetectors that can be readily incorporated into nanophotonic device integration. The device structure utilizes concentrated high electric field for enhanced efficiency and charge transport. The research on optimizing chemistry and conditions for quantum dot deposition will offer a route to increased speed, a major challenge for quantum dot devices. The utility of plasmonics to concentrate optical field and enhance quantum efficiency will help addressing the prevailing question of optical coupling in nanophotonics. If successful, the research will provide a first solution to fully integratable nanophotonic photodetection. Broader impact: The growing field of Nanophotonics has increased the demand for faster, smaller, and more sensitive on-chip photodetection. Given the divergence in materials and fabrication processes in nanophotonics, a nanoscale photodetector with full fabrication integratability has yet to be demonstrated. Success of this research could have a transformative impact in nanophotonic integrated circuits and broader fields of optical computing, communications and sensing. This research will also provide exciting multidisciplinary training opportunities for graduate and undergraduate students, and lead to broader impact to the society through diversity development, education and outreach activities.