Dimensional Control of Light Matter Interaction in Perovskite Chalcogenides: From Visible to Infrared Optoelectronics

Perovskite Chalcogenides are a new class of semiconductors, which have tunable band gap in the visible to infrared part of the electromagnetic spectrum. Besides this band gap tunability, they offer a unique opportunity to realize large density of states semiconductors with high carrier mobility. In this talk, I will discuss some of the advances made both in my research group and in the research community on the theory, synthesis of these materials and understanding their optoelectronic properties. The basic building block of the perovskite structure is the octahedral cage and the nature of its connectivity gives rise to both the perovskite and related structures with varying dimensionality. First, I will discuss how structure and chemical composition in Zr-containing perovskite sulfides can tune the optical properties in the visible spectrum, with an eye towards solar energy conversion. Second, I will discuss how the band gap can be further reduced to the infrared region for Ti-containing perovskite sulfides. I will also discuss about their anisotropic optical properties and large linear optical response. Finally, I will provide a general outlook for future studies on these exciting new class of materials.

 

References:
1.    Nature Photonics, 12, 392-396 (2018).
2.    Advanced Materials 29, 1604733 (2017).
3.    Chemistry of Materials, 30 (15), 4897-4901 (2018).
4.    Chemistry of Materials, 30 (15), 4882-4886 (2018).

 

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Jayakanth Ravichandran is an Assistant 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 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 the current position. His research interests are in materials design, synthesis, characterization, and physical properties of complex materials for electronic, photonic, and energy applications. He was named an Early Career Scholar by the Journal of Materials Research in 2017 and was a Link Energy Fellow.