Abstract:Tuning the Fermi level and complex dielectric function of low-dimensional nanophotonic structures including layered materials and nanoantenna arrays enables scientific exploration of quantum materials such graphene, phosphorene and topological insulators and, as well applications including electronic phase and amplitude modulators for the near infrared (conducting oxides) and mid infrared (graphene). We discuss light-matter interactions in materials and report dynamically tunable metasurfaces exhibiting >π phase modulation and ‘perfect’ absorption approaching 100%.
Teri Odom
Charles E. and Emma H. Morrison Professor of Chemistry
Associate Chair, Department of Chemistry
Northwestern University
Executive Editor, ACS Photonics
Title: Collective Nanoparticle Optics
Abstract:Metal nanostructures concentrate optical fields into highly confined, nanoscale volumes that can be exploited in a wide range of applications, from sensing to imaging. However, their broad far-field optical resonances increase in width as the particle size increases. To narrow these resonances while maintaining desirable near-field properties, we have developed unconventional procedures to organize the nanoparticles into arrays with spacings on the order of hundreds of nanometers, where narrow lattice plasmon resonances can result. This talk will describe a range of new optical phenomena that can emerge from nanoparticles arrays, from programmable and reversible plasmon mode tuning to superlatticeplasmons to achromatic flat lenses to dynamic, real-time tunable nanoscale lasing.
Edward Sargent
University Professor
Department of Electrical and Computer Engineering
Vice President-International
University of Toronto
Associate Editor, ACS Photonics
Title:Solution-processed photodetectors, solar cells, and optical sources based on quantum dots and perovskites
Abstract:Vast advances in materials and physical chemistry have led us to the point that, today, we can create a wide range of tunable, solution-processed materials whose spectral properties span the visible and infrared. These are enabling flexible solar cells, top-surface photodetectors, and ubiquitous light sources. This has in turn enabled rapid progress in the cost-effective conversion of solar energy into electrical power. These advances bring about a new challenge, namely, the need for massive (seasonal-scale) storage of energy. I will describe how the use of computational materials science, spectroscopies including ultrafast and synchrotron, and advances in materials chemistry, are accelerating the creation of new catalysts for CO2 reduction and oxygen evolution. I will discuss recent advances including a new high-activity OER catalyst and a low-overpotential CO2 reduction catalyst based on field-induced reagent
