Sukanya Ghosh
CUK, Tulmulla Campus
Sukanya Ghosh is an Assistant Professor in the Department of Physics at the Central University of Kashmir, India, and a Young Associate of the Indian Academy of Sciences (2024–2027). She is a theoretical physicist specializing in computational materials science and condensed matter physics. Her research focuses on first-principles modelling of two-dimensional (2D) materials, magnetism, and spintronic phenomena. She earned her Ph.D. from the Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, and has held postdoctoral positions at ICTP (Italy), Uppsala University (Sweden), and the University of Edinburgh (UK). Her current work explores quantum states in 2D magnetic systems and their potential spintronic applications.
Session 2A: Lectures by Fellows/Associates
Chairperson: Sanjay Kumar, BHU, Varanasi
Interplay of unusual structural reconstruction, exchange mechanism and electron correlation in high-temperature 2D van-der-Waals magnets
In recent years, the discovery of van der Waals (vdW) magnets has opened up numerous possibilities in fundamental science and technological applications. Their tunable structural, electronic, and magnetic properties make these materials promising candidates for low-power spintronic devices. Among these, the family of metallic magnets FenGeTe2 (where n = 3, 4, 5) has garnered significant attention due to their high Curie temperatures and fascinating physical characteristics. Our research on the FenGeTe systems began with an investigation into the unusual structural reconstructions observed in Fe5GeTe2, the most complex member of this family. By conducting density functional theory (DFT) calculations and Monte Carlo simulations, we discovered that the magnetic peculiarities associated with a specific iron (Fe) site are responsible for this structural behaviour. Once we resolved this puzzle, we became interested in exploring the entire FenGeTe2 family. However, we soon realized that the literature lacked a suitable computational approach to accurately capture the site-dependent electronic and magnetic properties, as well as the correct spectral features of these systems. The presence of Fe-site-dependent electron correlation effects further complicated this task. To address this, we employed three different ab initio approaches: (i) standard DFT, (ii) DFT with static electron correlation (DFT + U), and (iii) DFT combined with dynamic electron correlation effects (DFT + DMFT). Our results indicate that DFT + DMFT is the most accurate technique for capturing the many-body effects present in FenGeTe systems and reproducing the experimentally reported transition temperatures and spectral properties. Additionally, we explored ways to enhance the magnetism of this class of systems beyond room temperature. My talk will cover the intricate story of the FGT family in the monolayer limit, proposing their applicability in spintronic applications.