IMSE Seminar with Jayakanth Ravichandran on Chalcogenides
Phase change materials underpin many of the modern electronic and photonic technologies. The typical recipe for phase change materials is the presence of competing interactions between two or more degrees of freedom. This competition is enhanced in low dimensional materials. Many of the classic metal-insulator transitions such as charge density wave transitions are observed in low dimensional materials. In this talk, I will introduce a new class of materials known as quasi-1D hexagonal chalcogenides with face shared transition metal – chalcogen octahedra, especially BaTiS3. First, I will discuss the origin of large linear optical anisotropy in these materials in terms of birefringence, dichroism. Second, I will discuss the observation and possible explanations for density wave-like electronic transitions in BaTiS3. I will also discuss emerging understanding of the functionalities arising from subtle displacements in the atomic positions of these materials. Finally, I will provide a general outlook for future studies and applications of this exciting new class of materials.
References:
- Nature Communications, 11, 6039 (2020).
- Advanced Materials, 31 (33), 1902118 (2019).
- Nature Photonics, 12, 392-396 (2018).
- Chemistry of Materials, 30 (15), 4897-4901 (2018).
Faculty, students, and the general public are invited.