Rejuvenating a Versatile Photonic Material: Lithium Niobate

Speaker: Prof. Sasan Fathpour, Ph.D.
Affiliation: CREOL, The College of Optics and Photonics, University of Central Florida

Abstract: The excellent electrooptic and nonlinear-optical properties of lithium niobate (LiNbO3) have long established it as a prevailing photonic material for the long-haul telecom modulator and wavelength-converter markets. However, conventional LiNbO3 optical waveguides are low index-contrast, and hence bulky compared to modern integrated platforms such as silicon photonics. The bulkiness impedes photonic circuit implementations and imposes high optical power requirements for nonlinear applications. To address these shortcomings, thin-film LiNbO3 wafers and high-contrast waveguides (with submicron cross-sectional dimensions) were developed for the first time at CREOL in 2013. The thin films are heterogeneously integrated on silicon wafers and the technology is potentially compatible with silicon photonics foundry production. Since then, we have demonstrated a plethora of ultracompact integrated photonic devices and circuits (waveguides, microring resonators, modulators, grating couplers, wavelength converters, entangled photon sources, etc.) with significantly superior performances than the conventional LiNbO3 counterparts. More recently, commercial availability of the thin-film wafers has facilitated entering of several other research teams into this growing field. The overall efforts have rejuvenated LiNbO3 for novel electrooptic and nonlinear- and quantum-optic applications and the material is considered among the top candidates for heterogeneous integrated photonics. That is when multiple materials are monolithically integrated on the same silicon chip, while each material is chosen for the functionalities that suits it best. The progress in thin-film LiNbO3 integrated photonics, its future directions, opportunities, and challenges will be discussed.

Biography: Sasan Fathpour is a Professor at CREOL, The College of Optics and Photonics at the University of Central Florida (UCF). He also holds a secondary joint appointment at the Department of Electrical and Computer Engineering at UCF. He received a PhD degree in Electrical Engineering from the University of Michigan, Ann Arbor in 2005. He then joined the Electrical Engineering Department of UCLA as a postdoctoral fellow. Since joining the UCF faculty in 2008, he has received several university, national and international recognitions, including the NSF CAREER Award (2012) and the ONR Young Investigator Program Award (2013). Prof. Fathpour’s current research interests include heterogeneous integrated photonics, nonlinear integrated optics, silicon photonics, and unconventional photonic platforms operating in the mid-wave- and near-infrared and visible wavelength ranges. His team’s research at CREOL has been highlighted in Nature Photonics, Optics and Photonics News, Laser Focus World,, and several other trade magazines and professional websites. Prof. Fathpour is a co-author of over 170 publications, including 35 invited journal papers and conference presentations, 6 book chapters and 3 patents. In collaboration with Prof. Bahram Jalali at UCLA, he has co-edited the book Silicon Photonics for Telecommunications and Biomedicine, CRC Press. He is the cofounder of Partow Technologies, LLC, a spinoff company from his CREOL team’s research on thin-film lithium niobate photonics. He is a Fellow of The Optical Society, a Senior Member of IEEE and SPIE, and a Member of MRS.

For more information, contact Prof. Bahram Jalali ()

Date(s) - Sep 12, 2019
3:45 pm - 5:00 pm

E-IV Maxwell Room #57-124
420 Westwood Plaza - 5th Flr. , Los Angeles CA 90095