Keynote Speech

Precision Photon Manipulation: Ultrafast Detection and AI-Driven Multi- Dimensional Sensing and Imaging

Speaker:

M. Saif Islam

Department of Electrical and Computer Engineering

and The Center for Information Technology Research in the Interest of Society and the Banatao Institute (CITRIS)

Biography:

M. Saif Islam received his B.Sc. Degree in Physics from Middle East Technical University, an M.S. degree in Physics from Bilkent University, and Ph.D. degree in Electrical Engineering from UCLA in 2001. He worked for JDS Uniphase Corp and HP Labs before joining University of California- Davis in 2004, where he is a Professor in the Electrical and Computer Engineering Department and the Director of the Center for Information Technology Research in the Interest of Society (CITRIS) at UC Davis. His research in nanotechnology integrates low-dimensional and nanostructured materials into conventional semiconductor integrated circuits and systems. His work encompasses ultrafast optoelectronics for computing, 6G communication, quantum sensing, AI-enabled imaging, energy harvesting, and wide bandgap materials for harsh environment applications. Dr. Islam authored or co-authored more than 300 scientific papers, organized 35 conferences as a chair/co-chair, and holds 42 patents as an inventor/co- inventor. Prof. Islam received NSF CAREER Award, Outstanding Junior, Outstanding Mid-Career and Outstanding Senior Research Faculty Award of UC Davis Engineering, IEEE Professor of the Year and UC Davis Academic Senate Distinguished Teaching Award. He is a fellow of the American Association for the Advancement of Science (AAAS), Optical Society (Optica), International Society for Optics and Photonics (SPIE), Institute of Electrical and Electronics Engineers (IEEE) and National Academy of Inventors (NAI).

Abstract:

Photon-material interaction is generally very weak in most semiconductors when incident photon wavelengths are close to their optical bandgap. This leads to very weak absorption requiring considerably thick semiconductor films for efficient light absorption. However, a photodetector designed with a thick absorption region cannot operate at high speed due to a long carrier drift time. In this presentation, we will use a periodic array of micro and nanoscale surface structures to bend normally incident beams of photons into laterally propagating modes along the plane of semiconductor films. Such structures bend light beams, slow them down and contribute to unprecedented improvement in the light absorption efficiency in devices, even when designed with ultra-thin absorption regions. Slow and trapped photons offer exciting application opportunities such as ultra-fast photodetectors for data center communication, sensors for advanced bioimaging, LiDAR, and highly efficient solar cells. A compact assembly of such photodetectors, incorporating specialized surface nanostructures, holds the potential to significantly enhance imaging capabilities by acquiring multi-dimensional data, including spectral profiles, temporal responses, and spatial resolution. This advancement is achievable by engineering individual ultrafast detectors exhibiting distinct responses to identical illumination while leveraging artificial intelligence (AI)- driven computational imaging. This talk will demonstrate how these capabilities can substantially miniaturize the physical dimensions of existing imaging and spectroscopic systems and elevate overall system sensitivity. These advancements can be applied to various fields, including noninvasive real-time detection and monitoring of molecules for medical diagnostics, biological sensing, and food quality assessment.