Optical Properties and Optoelectronic Applications of Nano-Size Metallic Films and Metamaterials

This talk presents new optical materials and device concepts for future optoelectronic device platforms, aiming at compact size, high efficiency and robust performance. A new kind of silver film: aluminum-doped silver is discovered and its properties are studied. The film is ultra-thin, ultra-smooth, low loss, and is thermally robust and long-term stable, which facilitate high performance optoelectronic devices such as organic solar cells, optical metamaterials, and nano-photonic/plasmonic devices. Metamaterials are artificially designed materials with extraordinary optical properties and have the potential to replace conventional bulky optical systems. Nano-size metamaterials are demonstrated for optical spectrum filtering (structured color filter) and polarization/direction control (asymmetric transmission and polarization conversion metasurface). In the end, nano-imprinting lithography and its application in fabricating polymer based photonic devices will also be discussed.