Tailoring Electromagnetic Waves from RF to the IR: Theory and Applications
Assoc. Prof. J. Sebastian Gomez-Diaz
University of California, Davis
Abstract: This talk presents novel approaches to manipulate electromagnetic waves and exploit them in practical applications. The first part of the talk will be dedicated to discuss the possibilities enabled by time-modulation to implement a wide variety of low-loss nonreciprocal microwave components exhibiting fascinating functionalities, including (i) phased-array antennas that independently control their transmission/reception radiation patterns at the same operation frequency; (ii) gradient metasurfaces able to arbitrarily manipulate beams propagating in free-space; (iii) bandpass filters that behave as isolators on one direction of the wave propagation; and (iv) power dividers and Yagi-Uda planar antennas, among other devices. The second part of the talk will focus on the use of RF microelectromechanical systems (MEMS) for infrared sensing. Specifically, I will describe our latest effort to merge RF MEMS devices with ultrathin metasurfaces to detect IR waves with desired wavelengths while providing ultralow noise and high responsivity at room temperature. Then, I will overview our design strategy to improve the devices perform, stressing challenges and opportunities, and discuss our state-of-art automatized characterization system able to test hundreds of IR sensors in a short time span. I will conclude by outlining the exciting applications enabled by this promising technology, with focus on gas sensing and cancer detection.
Speaker’s Bio: J. Sebastian Gomez-Diaz is an Associate Professor in the Electrical and Computer Engineering Department at the University of California, Davis. He received his Ph.D. degree in electrical engineering (with honors) from the Technical University of Cartagena (UPCT, Spain) in 2011 performing parts of his graduate work at the Ecole Polytechnique de Montreal (Canada) and the Fraunhofer Institute (Germany. He developed his post-doctoral work at the École Polytechnique Fédéral de Lausanne (EPFL, Switzerland) funded by a Marie Currie Fellowship, and at the Metamaterials and Plasmonic Research Laboratory of The University of Texas at Austin (US). His work has been funded by NSF, DoD, SRC, the Keck Foundation, and NIH. Dr. Gomez-Diaz has received several recognitions, including the NSF CAREER Award in 2018 and the Leopold Felsen Award for Excellence in Electrodynamics in 2017. His main research interests include multidisciplinary areas of electromagnetic wave propagation and radiation, metamaterials and metasurfaces, plasmonics, 2D materials, non-linear and non-reciprocal phenomena, and other emerging topics on applied electromagnetics and nanotechnology.