A5063928546- Multiferroics and related materials
- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Fusion materials and technologies
- Nuclear reactor physics and engineering
- Nuclear and radioactivity studies
- Nuclear Materials and Properties
- Dielectric properties of ceramics
- Ferroelectric and Piezoelectric Materials
- Solid-state spectroscopy and crystallography
- Manufacturing Process and Optimization
- Semiconductor materials and devices
- Graphite, nuclear technology, radiation studies
- Advanced Surface Polishing Techniques
- Electronic Packaging and Soldering Technologies
- Advanced Manufacturing and Logistics Optimization
- TiO2 Photocatalysis and Solar Cells
- Superconducting Materials and Applications
- Electronic and Structural Properties of Oxides
- Crystal Structures and Properties
- Microstructure and mechanical properties
University of Augsburg
2012-2017
University of Tübingen
2015
Skyrmions are whirl-like topological spin objects with high potential for future magnetic data storage. A fundamental question that is relevant to both basic research and application whether ferroelectric (FE) polarization can be associated skyrmions' texture these manipulated by electric fields. We study the interplay between magnetism in lacunar spinel GaV4S8, which undergoes a structural transition orbital ordering at 44 K reveals complex phase diagram below 13 K, including ferromagnetic,...
We present a dielectric spectroscopy study of the polar dynamics linked to orbitally driven ferroelectric transition in Skyrmion host GaV(4)S(8). By combining THz and MHz-GHz techniques, we succeed detecting relaxational arising from coupled orbital fluctuations this material trace its temperature dependence paraelectric as well phase. The relaxation time significantly increases when approaching critical both sides transition. It is natural assume that these map at Jahn-Teller Because...
We deduce the intrinsic conductivity properties of ferroelectric domain walls around topologically protected vortex cores in multiferroic YMnO_{3}. This is achieved by performing a careful equivalent-circuit analysis dielectric spectra measured single-crystalline samples with different densities. The contrast between bulk domains and less conducting boundaries revealed to reach up factor 500 at room temperature, depending on sample preparation. Tunneling localized defect charge carriers...
Insulating helimagnetic Cu2OSeO3 shows sizeable magnetoelectric effects in its skyrmion phase. Using magnetization measurements, magneto-current analysis and dielectric spectroscopy, we provide a thorough investigation of coupling, polarization constants the ordered magnetic polar phases single-crystalline external fields up to 150 mT at temperatures below 60 K. From these measurements construct detailed phase diagram. Especially, metamagnetic transition helical conical spin order are...
In the present work, we provide results from specific heat, magnetic susceptibility, dielectric constant, ac conductivity, and electrical polarization measurements performed on lacunar spinel $\mathrm{Ga}{\mathrm{V}}_{4}\mathrm{S}{\mathrm{e}}_{8}$. With decreasing temperature, observe a transition paraelectric paramagnetic cubic state into polar, probably ferroelectric at 42 K followed by ordering 18 K. The polar is likely driven Jahn-Teller effect due to degeneracy of ${\mathrm{V}}_{4}$...
The lacunar spinel GaV4S8 exhibits orbital ordering at 44 K and shows a complex magnetic phase diagram below 12.7 K, which includes ferromagnetic cycloidal spin order. At low but finite external fields, Néel-type skyrmions are formed in this material. Skyrmions whirl-like vortices that have received great theoretical interest because of their non-trivial topology also considered as basic entities for new data-storage technologies. Interestingly, we found the orbitally ordered sizable...
The lacunar spinel GeV4S8 undergoes orbital and ferroelectric ordering at the Jahn-Teller transition around 30 K exhibits antiferromagnetic order below about 14 K. In addition to this orbitally driven ferroelectricity, spinels are an interesting material class, as vanadium ions form V4 clusters representing stable molecular entities with a common electron distribution well-defined level scheme of states resulting in unique spin state per molecule. Here we report detailed x-ray, magnetic...
We report on THz time-domain spectroscopy multiferroic ${\mathrm{GeV}}_{4}{\mathrm{S}}_{8}$, which undergoes orbital ordering at a Jahn-Teller transition 30.5 K and exhibits antiferromagnetic order below 14.6 K. The experiments are complemented by dielectric audio radio frequencies. identify low-lying excitation close to 0.5 THz, is only weakly temperature dependent probably corresponds molecular within the electronic level scheme of ${\mathrm{V}}_{4}$ clusters. In addition, we detect...
Contrary to controlled experiments in a laboratory, robotics competitions pose real challenge an intelligent autonomous system. To allow good performance, robotic systems have be very robust unforeseen circumstances highly constrained time frame. In this paper we present the design, implementation and performance of system developed for participation SICK robot day 2014, with which achieved results, placing second, same maximum score as first. The task competition was alternately fetch...