Metal-to-Insulator Phase Transition in 2D Semiconductor and Application of 2D Materials for Electrostatic Energy Storage (06/01/25)
Speaker and Affliation:
Dr.Nihar Pradhan, Professor
Department of Physics, Jackson State University, Jackson, MS, United States
When?
06th January, 2025 (Monday), 11.00 AM (India Standard Time)
Where
KI Vasu Auditorium, Dept. of Materials Engineering, IISc, Bangalore
Abstract:
Layered two-dimensional materials have attracted significant interest due to their unique electronic properties. In this talk, I will discuss the electrical transport properties of few-layered transition metal dichalcogenides (TMDs) showing insulator-to-metallic phase transition under applied electric field. Charge carrier mobility of a few layered ReS2 and MoSe2 FET devices increases as a function of decreasing temperature. Despite defects and impurities, evidence of a metallic state was observed at low temperature using an applied gate voltage or, equivalently, increasing the density of charge carriers within the 2D channel. We analyzed the conductivity data to explore the nature of the phase transition using temperature scaling analysis to distinguish the QPT and percolation nature of phase transition. In the second part of my talk, I will provide an overview of our recently developed high-density capacitive energy storage device on 2D nanofiller based dielectric polymer nanocomposites thin film capacitor where 2D fillers are placed in a stratified manner in the polymer matrix to improve the polarization and breakdown strength of the dielectric capacitors.
About the Speaker :
Dr Nihar Pradhan is an Associate Professor in the Department of Physics at Jackson State University, Mississippi, United States. He graduated with a PhD degree in Applied Physics from Worcester Polytechnic Institution, Massachusetts, USA and subsequently did postdoctoral work at University of Massachusetts and National High Magnetic Field Laboratory, Florida. His research interests span from material science to engineering working in interdisciplinary research projects based on two dimensional materials systems. His expertise is in synthesis of layered semiconducting materials, device fabrication using 2D materials and their heterostructures, exploring their electronic and optical properties to explore the interface science. Some of his current projects focus on exploring interface science in 2D-2D and 2D-3D heterostructure systems to develop energy efficient electronic devices, such as transistors, p-n junction and logic devices.
Dr Pradhan has authored 87 peer review publications with three United States Patent. His research is funded by several funding agencies, including the National Science Foundation, Department of Defense, Department of Energy, Airforce Research office and Princeton University. He is the director of the recently funded collaborative grant from the Department of Energy to develop “Heterogeneous Integration of 2D-3D Materials for Energy Efficient Electronics”. He is serving as the Associate Editor and editorial board member of Springer nature Journal “Emergent Materials” and “Scientific Reports”. He is also a recipient of DOE visiting faculty awards at Argonne National Lab and National High Magnetic Field Laboratory. He serves as the vice president of user facility at Center for Nanoscale Materials, Argonne National Laboratory, Chicago.