Licentate thesis: Analysis of time-dependent systems described with a complex-scaled Hamiltonian

by Jakob Bengtsson (Stockholm University, Department of Physics)

Thursday 4 Jun 2009, 13:15 → 15:15 Europe/Stockholm

FD51

During the last decades, the laser technology has gone through a series of revolutionary improvements. With light pulses in the subfemtosecond regime being experimentally available nowadays, it is often indispensable t deal with an explicity time-dependent Hamiltonian for a proper theoretical description of the interactions of atoms with such pulses. This leads to a significant increase of the computational workload, which motivates the search for new numerical methods and algorithms to approach time-dependent problems. This thesis presents contributions to this aspect, with the main focus on the use of complex-scaled Hamiltonians. The formalism of complex scaling is studied in the context of its application to a simple but explicity time-dependent atomic system, a hydrogen-like atom exposed to short laser pulse. Both the non-relativistic dynmics are investigated, and the numerical advantages as well as possibilities to extract physical quantities from a complex-scaled wave function are discussed.