Major Areas of Research

Our research aims to provide fundamental insight into the relation between the properties of excitons and charge carriers and the physico-chemical structure of materials. In order to achieve this a variety of time-resolved techniques are used. Charge carriers and electronically excited states are generated using pulsed laser systems or an electron accelerator. The properties of these charges and excited states are studied on times scales ranging from femtoseconds to microseconds by optical spectroscopy, microwave/terahertz conductivity measurements, and several other opto-electronic techniques. The experimental work in the section is supported by theoretical studies, including electronic structure calculations, molecular dynamics simulations and simulations of charge and exciton transport.   

Charge carrier multiplication in semiconductor nanoparticles

The dynamics of excitons and charges in semiconductor nanoparticles (quantum dots) are investigated by femtosecond transient optical absortion measurements and by terahertz conductivity experiments.

Charge transport along isolated molecular wires

Time-resolved microwave conductivity measurements are performed in order to study the motion of charges along isolated conjugated polymer chains in solution.

 

Charge transport in solid nano-structured materials

The charge transport properties of organic and inorganic materials for opto-electronic applications are studied in the solid state by microwave conductivity measurements. The charges are either generated in the bulk solid by irradiation with an electron accelerator or in thin films by photoexcitation.

 

Optical properties of charged species in opto-electronic materials

The optical absorption spectra of charged species in materials for optoelectronics are studied by nano-second time-resolved optical absorption spectroscopy.

 

Exciton diffusion and dissociation in hybrid organic/(in)organic systems for photovoltaics

The dynamics of excitons and charges in organic/(in)organic combinations of materials are studied in thin films, either on the nanosecond time scale by time-resolved microwave conductivity measurements on a femtosecond time scale by transient optical or terahertz absorption experiments.

 

Computational studies of opto-electronic materials

Theoretical studies are carried out to understand and predict  the nature and dynamics of charge carriers and excitons in opto-electronic materials.
 

 

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