Title:	Dynamical phenomena in functional materials
DNr:	SNIC 2019/2-33
Project Type:	SNIC Large Compute
Principal Investigator:	Biplab Sanyal <biplab.sanyal@physics.uu.se>
Affiliation:	Uppsala universitet
Duration:	2020-01-01 – 2021-01-01
Classification:	10304 10302 10403
Homepage:	http://katalog.uu.se/empinfo/?id=N1-83
Keywords:

Abstract

The focus of this project is to carry out simulations to understand several dynamical phenomena in a variety of functional materials useful for technological applications. This project is a continuation of the SNAC large-scale allocation of the previous year on correlated multiferroic oxides, their magnetization and polarization dynamics and the study of excited state dynamics in functional materials like novel 2D systems, organic-inorganic interfaces etc. The motivation of the first part of the project is the application of theoretical tools to understand and predict the complex properties of multiferroic oxides. The specific aim is to combine ab initio calculations and atomistic spin dynamics simulations for studying magnetization and polarization dynamics in multiferroic oxides on the same footing. Apart from that, a general understanding of the interfaces of correlated oxides is another important topic, which is carried out in collaboration with experimental groups. In recent times, there has been a tremendous interest in the research community in developing suitable routes for realizing green energy sources for the need of human mankind in near future. However, the mechanisms of transfer of electrons and holes in the reactions involved in the processes of energy production are very complex and yet to be understood properly. This forms the second part of the project. The vast abundance of sunlight gives us the opportunity to convert solar energy to electricity and chemical energy through hydrogen production by water splitting, photocatalysis and photosynthesis. In all these areas, ultrafast charge transfer process plays an important role. Though the experimental field has progressed quite significantly in the last decade in studying charge transfer dynamics by femtosecond pump probe techniques coupled with core-hole clock method in the realm of x-ray spectroscopy, femtosecond transient absorption spectroscopy, time dependent fluorescence spectroscopy etc., the theoretical understanding of the ultrafast charge transfer processes via quantum mechanics is still inadequate. The complexity lies in the time dependent description of coupled electron and ion dynamics that occurs non-adiabatically. The adiabatic charge transfer and relaxation processes are not suitable to describe photoactive systems where a transition between different electronic levels occurs due to photon absorption. In this proposal, we aim to study ultrafast charge transfer processes by density functional theory and non-adiabatic molecular dynamics simulations and apply in a variety of problems related to solid state materials. Moreover time-dependent density functional theory (TDDFT) will be used to study optical absorption spectra, high harmonic generation and ultrafast charge transfer dynamics in 2D materials and their heterointerfaces.