Materials World Network: Nanoscale Structure and Shaping of Ferroelectric Domains

• Applicants: Professor Dr. Karsten Buse; Professor Dr. Wolfgang Sohler
• Subject Area: Synthesis and Properties of Functional Materials
• Term: from 2006 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 24840618

Improved understanding of nucleation and growth of ferroelectric domains especially in lithium niobate and lithium tantalate crystals and waveguides, innovative methods for domain structuring and for domain wall investigation, as well as development of devices that utilize sub-micron- and nano-sized domain structures in these materials are the goals of this transatlantic research project with contributions from five groups: Simon Phillpot (University of Florida) with theoretical modelling of ferroelectric domain walls, Volkmar Dierolf (Lehigh University) with rareearth and Raman spectroscopy to monitor the structure and dynamics of domain walls and with light-aided writing of domain patterns, Karsten Buse (University of Bonn) with the observation of domain nucleation on the fast and ultrafast time scale applying pump-and-probe techniques, with writing of sub-wavelength domains by nonlinear processes, and with the realization of an electro-optically controlled Bragg reflector, Venkatraman Gopalan (Penn State University) with scanningprobe tools to pattern and to detect domains and with the realization of photonic band-gap superprisms based on nano-domain structures, and Wolfgang Sohler (University of Paderbom) with the writing of (sub-)micron domain patterns in the surface and in the bulk of (ridge) waveguides in lithium niobate substrates using electric field-, temperature- and light-assisted poling techniques, and with the development of integrated-optical parametrical oscillators with backward nonlinear coupling offering new tuning and spectral properties in the mid-infrared spectral range.

• DFG Programme: Research Grants
• International Connection: USA
• Participating Persons: Professor Dr. Volkmar Dierolf; Professor Venkatraman Gopalan; Professor Simon Phillpot