Optical Metamaterials: from Linear Responses to Nonlinear Interactions and beyond

Metamaterials are commonly viewed as artificially-structured media capable of realizing arbitrary effective parameters, in which metals and dielectrics are delicately combined to facilitate the index contrast and plasmonic response required for a particular purpose. We aim to drive beyond this limited vision and explore the use of optical metamaterials as a generalizable platform for optoelectronic information technology: Metals will provide tailored plasmonic behavior as before, but will serve double duty by providing electrical functions including voltage input, carrier injection/extraction, and heat sinking, and dielectrics will consist of functional elements such as Kerr materials, electrooptic polymers, and p-n junctions. In this talk I will discuss our preliminary results on several topics in this category, including the electrically induced harmonic generation and optical rectification of light in a perfect metamaterial absorber, the nonlinear spectroscopy and imaging from a chiral metamaterial, and the backward phase-matching in an optical metamaterial where the fundamental and frequency-doubled waves possess opposite indices of refraction.

Biography

Wenshan Cai received his B.S. and M.S. degrees in Electronic Engineering from Tsinghua University, Beijing, China in 2000 and 2002, respectively, and his Ph.D. in Electrical and Computer Engineering from Purdue University, West Lafayette, Indiana, in 2008. He joined the faculty of the Georgia Institute of Technology in January 2012 as an Associate Professor in Electrical and Computer Engineering, with a joint appointment in Materials Science and Engineering. Prior to this, he was a postdoctoral fellow in the Geballe Laboratory for Advanced Materials at Stanford University. His scientific research is in the area of nanophotonic materials and devices, in which he has made a major impact on the evolving field of plasmonics and metamaterials. Dr. Cai has published ~40 papers in peer-reviewed journals, and the total citations of his recent papers have reached ~4,000 within the past few years. He is a reviewer or editorial board member of over 20 scientific journals. In addition, Dr. Cai is the lead author of the book Optical Metamaterials: Fundamentals and Applications (Springer, 2010), a text or a major reference used at many universities around the world, for which he won the 2014 Joseph W. Goodman Book Writing Award from OSA and SPIE.