10/04/2024
By Amanda Vozzo
Speaker: Christopher Roberts, Technical Staff Member, Optical Engineering, MIT Lincoln Laboratories
Title: “Phase-Change Materials & Tunable Optical Devices”
Abstract: Many applications demand reconfigurable optical behavior, from imaging & sensing to optical displays. Traditional free-space optics based on lenses and filters can be bulky and require complex system design and bulky opto-mechanics to incorporate multiple functionalities. Recently, chalcogenide-based optical phase change materials (oPCMs) have displayed large, non-volatile, changes in refractive index (Δn>1) while maintaining broad a broad IR optical transparency window. The source
of the large contrast is due to a thermally-driven reversible material phase transitions between amorphous and crystalline states. oPCMs can be combined with an array of integrated optical devices from photonic integrated circuits to meta-optics providing a new generation of tunable optical devices.
Bio: Christopher Roberts is a Technical Staff member in the Optical Engineering group at MIT Lincoln Laboratory, where he is exploring novel optical technologies and materials to enable the next generation of optical systems. His current research interests include: phase-change optical materials, meta-optics and metamaterials, micro-optics, energy harvesting, AI-assisted engineering, and novel computing paradigms.
Roberts received his B.S. in Astrophysics at the University of Massachusetts Amherst, where his research focused on instrumentation for mm-wave astronomy. He received his M.S. & Ph.D. in Physics at the UMass Lowell in the Multiscale Electromagnetics Group with a focus on theoretical & computational photonics of metamaterials and diffractive structures.