Development of the time-dependent GW method

The aim of the proposed project is to develop a theoretical and computational scheme for studying the dynamics and non-equilibrium properties of quantum many-particles systems and real materials under the influence of a time-dependent potential from first-principles.

The scheme combines the GW approximation, a method of choice for calculating the electronic structure of materials under equilibrium conditions, and Floquet theory for treating time-periodic potentials.

Unlike model studies, the scheme will allow access to a wide landscape of new unexplored possibilities of studying the time-dependent behaviour of electrons and ions in real materials without adjustable parameters. For example, new metastable states can emerge which cannot materialize under equilibrium conditions.

By introducing the concept of time-supercell approach, the scheme will be extended to treat an arbitrary time-dependent potential of finite duration such as pulses used in time-resolved photoemission experiments. This circumvents the computationally expensive approach of solving the integro-differential Kadanoff-Baym equations.

Time wise, the first two years will be spent on theoretical and code development while the last two years on applications.

Future extension of the scheme to treat strongly correlated materials based on the recently developed GW+DMFT will also be considered. The proposed project is highly suitable as a thesis work and it is planned to be carried out with a doctoral student.