Quasi-1D Hexagonal Chalcogenides: A Novel Materials Platform for Next Generation Infrared Opto-electronics
Mork Family Department of Chemical Engineering and Materials Science,
Ming Hsieh Department of Electrical and Computer Engineering,
University of Southern California
Jayakanth Ravichandran is an Associate Professor in the Mork Family Department of Chemical Engineering and Materials Science with courtesy appointment in Ming Hsieh Department of Electrical and Computer Engineering at University of Southern California. He holds the Philip and Cayley MacDonald endowed early career chair. He received his Ph.D. degree from University of California, Berkeley in 2011. He performed post-doctoral research at Columbia University and briefly at Harvard University, before joining USC in 2015 as an Assistant Professor. His research interests are in materials design, synthesis, characterization, and physical properties of complex materials for electronic, photonic, and energy applications. His honors include the 2020 TMS Young Leader Professional Development Award, and 2017 Early Career Scholar in Materials Science by the Journal of Materials Research.
Infrared opto-electronics is at crossroads, where very mature II-VI and thermal detector technology dominates the detector markets with much of the focus on the scaling and device advances over materials. Nevertheless, the sustained growth of infrared optoelectronics relies on the development of novel materials with additional functionalities in the modulation and sensing of infrared light. To this end, in this talk, I will introduce a new class of materials known as quasi-1D hexagonal chalcogenides as a new semiconducting platform with large optical anisotropy in the mid- and long-wave infrared energies. First, I will discuss the origin of large linear optical anisotropy in BaTiS3 in terms of birefringence, dichroism. Second, I will discuss the role of modulations in Sr1+xTiS3 towards dramatic improvements in the optical anisotropy. Lastly, I will also discuss our efforts in understanding the anisotropic photoconductance response towards polarization sensitive infrared detection. Finally, I will provide a general outlook for future studies and applications of these exciting new class of materials.
Nature Photonics, 12, 392-396 (2018).
Chemistry of Materials, 30 (15), 4897-4901 (2018).
Advanced Materials, 31 (33), 1902118 (2019).