Ph.D Thesis

Ph.D StudentPreezant Yevgeni
SubjectRecombination in Molecular Films
DepartmentDepartment of Electrical and Computer Engineering
Supervisor PROF. Nir Tessler


Semiconducting polymers is vivid field of research under active experimental and theoretical development. Recently semiconducting polymers were used in commercial applications mainly as light-emitting elements. In spite of commercial success there are several open physical questions in this field. One of the many is a problem of the strong concentration dependence of the recombination constant. It has been demonstrated experimentally by several independent researches using different experimental methods that the recombination constant is approximately proportional to the first power of concentration. Starting from the simple first-principle physical model describing the transport in the polymeric media as the hopping transport through energetically disordered manifold of localization states, we developed and approved new computational approach allowing to treat in a coherent manner both transport and recombination. We explain experimentally observed dependencies and demonstrate the power of the simulation approach simulating complicated spatial and energetic transients for arbitrary concentrations and fields.

During the work we develop and demonstrate an experimental technique allowing investigating the recombination for arbitrary concentrations and field strength combinations.