Dissertation Defense

Manipulating light at micro- and nano-scale: enable photonic structures toward real-world applications

Chengang Ji


Recent advances in fabrication and processing methods have spurred many breakthroughs in the field of nano- and micro-structures that provide novel ways of manipulating light interaction in a controllable manner, thereby enabling various innovative applications. This thesis investigates new photonic design concepts and materials featuring high performance and long-term stability for bridging the gap between the research and the real-world applications.

Firstly, angle-insensitive structural color filters are studied employing various mechanisms. The proposed structures offer significant advantages over existing colorant-based filters in terms of high efficiency, slim dimension, and being free from photobleaching. They have been successfully adapted into practical applications including decorative paints and highly-efficient colored photovoltaics. In addition, optical designs are incorporated into vehicle interiors, opening up a new path to the extensive use of optics in automobiles: Anti-glare colored dashboard with the potential for high-resolution dashboard displays are demonstrated with micro-scale lenticular lenses; Invisible vehicle pillars for safe driving are realized with compact optical cloaks using different optical components, including polarizers and mirrors. The next part is the research into a cost-effective and easy-to-fabricate method for flexible transparent electrodes employing ultra-thin, ultra-smooth, and low-loss copper-doped silver. This novel silver alloy requires only room-temperature deposition and presents outstanding optical and electrical properties, mechanical flexibility, and environmental stability, which are greatly desired in future high-performance flexible optoelectronic devices.

Sponsored by

L. Jay Guo