Research & Facilities

Hybrid materials are materials prepared by combining organic and inorganic materials designed on the micro or nano scale. The combination of such materials leads to new exciting functionality and effects with highly tailorable properties. For the fabrication of inorganic materials we use sol-gel-based processes. Our focus is currently on wide-band-gap semiconductors, such as silicon carbide (SiC), titanium dioxide (TiO2) or zinc oxide (ZnO) which are very promising materials for numerous photonic applications. Various growth conditions lead to nano or micro crystals and fibers. Above all also porous and bulk semiconductors are grown.

The development of new materials needs a deep understanding of the materials properties. Thus various kinds of spectroscopy are needed. Among common optical spectroscopy, our field of expertise is magnetic resonance spectroscopy with various techniques such as optically or electrically detected multiple resonance spectroscopy, allow the determination of the microscopic structure and chemical nature of defects in materials. The knowledge of defects in materials is important for a detailed understanding of electrical and optical properties of materials and thus allows the application of such defects for device application.

Photonic Crystals

Photonic crystals are usually viewed as an optical analogue of semiconductors that modify the properties of light similarly to an 'atomic' lattice that creates a semiconductor band-gap for electrons. Photonic crystals are periodic dielectric or metallo-dielectric structures in which the…


Metamaterials are artificial optical materials where the effective permeability (µ) and permittivity (ɛ) can be adjusted. Classical metamaterials have an adjustable positive µ and ɛ. They consist e.g. of coils and inductors far away from their resonance. However, close to the resonance of…

Sol-gel-based semiconductors …

The group has extensive experience in the development of sol-gel routes for the fabrication of wide-bandgap semiconductor materials. Among others silicon carbide (SiC), titanium dioxide (TiO2) and zinc oxide (ZnO) are of main interest. Depending on the sol-gel annealing procedure one obtains…

Magnetic Resonance Spectroscopy…

Defects, even as contamination with extremely low concentration, may strongly determine the electrical and optical properties of materials. Thus, the knowledge of the chemical nature and their microscopic structure is important either to avoid them or to use them technologically. A powerful…


Prof. Dr. Siegmund Greulich-Weber

University of Paderborn
Faculty of Science
Department of Physics
Warburger Straße 100
33098 Paderborn

Tel.: +49 5251 60-2740
Fax: +49 5251 60-3247
E-mail: greulich-weber[at]