Light-Matter Interactions

The Lewis Group is part of the "Light-Matter Interactions in Energy Conversion" Energy Frontier Research Center. The LMI-EFRC is a national resource for fundamental optical principles and phenomena relevant to solar energy conversion, and for design of the optical properties of materials and devices used for energy conversion. The LMI-EFRC features a team that spans the campuses of the California Institute of Technology, the University of California at Berkeley, and the University of Illinois at Urbana-Champaign. This collaboration creates a partnership between scientific leaders in optical properties of matter with experts in solar photovoltaic and photochemical energy conversion and innovators in the design and fabrication of novel electronic and photonic materials.

The vision of the LMI-EFRC is to tailor the morphology, complex dielectric structure, and electronic properties of matter so as to sculpt the flow of sunlight and heat, enabling light conversion to electrical and chemical energy with unprecedented efficiency. Considerable scientific effort has been devoted in recent years to understanding the absorption, propagation, nonlinear interactions, localization and dispersion of light in complex optical structures, such as photonic crystals, photonic band gap media, plasmonic materials, and metamaterials. Likewise, over four decades, enormous effort has been devoted to photovoltaic and other light-energy conversion devices, and also to the realm of communications technology, to the study of optoelectronic devices such as lasers, waveguides, electro-optic devices, and photodetectors. However, to date there has been remarkably little interplay between any of these fields. We are now entering an era when insights about the flow of light in materials can be harnessed to precisely and efficiently guide optical energy to nano-structured absorbers, enabling revolutionary advances in photovoltaic energy conversion and photoelectrochemical fuel synthesis from sunlight.

The design, fabrication and characterization of complex, heterogeneous three-dimensional photonic materials is an enormous challenge that lies at the intersection of optical physics, chemistry and materials science. The LMI EFRC interdisciplinary approach relies on the interplay of fundamental insights about the physics of photon-matter interactions, innovative materials synthesis, and recognition of the opportunities for application in future photovoltaic and photoelectrochemical energy conversion.

Areas of research in the LMI-EFRC include:

• Visible and Ultraviolet Generation by Cooperative Upconversion
• Metal Optics for Spontaneous Emission and Absorption Enhancement
• Transformation Optics for Photovoltaics
• Self-Architected and Complex Architecture Absorbers