Experimental Physics II - Research
Main points of research
Transition metal oxides are a focal point of our research as they are of high fundamental and technical interest due to their great diversity of physical properties.
Many of those compounds are electronically correlated and show interesting phenomena like high temperature superconductivity, metal-insulator transitions or "colossal" magnetoresistance in dependence on temperature, pressure or doping.
The physical mechanisms behind these effects are a very active field of theoretical and experimental investigations since decades.
Often, however, the basic interactions are still unclear.
The work of our chair is concentrated on the field of electronic, magnetic and structural properties of transition metal oxides. The compounds are analysed in form of thin films, single crystalline and polycrystalline bulk samples as well as nanocrystalline particles.
Fundamental Research
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Fibre reinforced materials
Fibre reinforced materials are the most promising composites due to their superior mechanical properties, their high potential in light weight construction and their versatility for integration of functions. -
Non-destructive testing
Ultrasonic microscopy and acoustic emisssion analysis can be applied for non-destructive testing on hybrid materials. For coated fiber-reinforced materials different damage mechanisms were separated using pattern recognition techniques which were used to determine mechanical strength of different coating types. -
Preparation and characterization of nanoparticles
Nanostructured materials can be expected to show size dependent electronic, optical, chemical and magnetic properties. To investigate the properties of the particles it is necessary to prepare them within a narrow size distribution. -
Superconducting Proximity Effect in Superconductor/Ferromagnet (S/F) Nanolayered Structures
Singlet superconductivity and ferromagnetism are usually not expected to coexist, because superconductivity requires the anti-parallel alignment of electron spins to form Cooper pairs, whereas in the ferromagnetic state electron spins are aligned parallel. Fulde-Ferrell and Larkin-Ovchinikov (FFLO) predicted that, nevertheless, superconducting pairing may occur on a ferromagnetic background, but with a non vanishing momentum of the Cooper pair. Such FFLO-like pairing could be realized in S/F layers, leading to a variety of novel physical effects, such as an oscillation of the critical temperature with increasing F-layer thickness or an extinction and recovery of superconductivity by an interference of the superconducting pairing wave function. -
Transmission-Electron-Microscopy (TEM)
Transmission-Electron-Microscopy in combination with Energy Dispersive X-ray Analysis (EDX) and Electron-Enenergy-Loss-Spectroscopy (EELS) is used for structural and chemical analysis on nm-scale. -
Electronic transport properties of materials at low temperatures and high pressure
Measurement of electrical resistivity, Hall effect and Seebeck effect are performed in a temperature range from 0.008 K to 350 K and in magnetic fields of up to 17 T. Electrical resistivity can be measured at an external pressure (that can, among others, induce a metal to insulator transition) of max. 25 GPa. -
Single crystal growth of metal oxides and sulfides
Single crystals are synthesized by different procedures like chemical transport or flux methods. The crystals are characterized via X-ray diffraction and measurement of the magnetic susceptibility. -
Preparation of thin films
Metal oxides in form of thin films are prepared by spray pyrolysis or evaporation and characterized with methods like Scanning Electron Microscopy (SEM) or Scanning Force Microscopy (AFM). -
Electronic and Structural Properties of Surfaces
The properties of surfaces of single crystals and thin films are analysed with methods like photoelectron spectroscopy and atomic force microscopy.
Institution Title Runtime DFG Relation of electromagnetic and acoustic emission to temporal and spatial crack motion on a microscopic scale in polymers and carbon fibers 2012-2014 DFG Study of the Superconducting Proximity Effect Spin-Wave Phenomenon in Superconductor/Ferromagnet Nanolayered Structures 2010-2012 DFG (SFB 484) Untersuchung zeitlicher und räumlicher Korrelationen mittels Neutronen- und Röntgenstreuung 2006-2009 DFG (SFB 484) Elektronische Transporteigenschaften in der Nähe von Metall-Isolator-Übergängen 2006-2009
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Applied research
In cooperation with various companies and with the "Anwenderzentrum Material- und Umweltforschung" we pursue projects in the field of applied research.
Some topics are listed in the following table:Institution Title Runtime BMBF, Spitzenclusterwettbewerb MAI Carbon: Carbon Composites - Schlüsseltechnologie für Deutschland 2012-2017 Bayerische Forschungsstiftung CFK/Metall-Mischbauweisen im Maschinen- & Anlagenbau - FORCIM3A 2011-2014 Bayerisches Staatsministerium für Wirtschaft, Infrastruktur, Verkehr und Technologie (Forschungsprogramm "BayernFIT") ISAR – Innovativer Spinformprozess für hochfeste Aluminiumlegierungen und Rührreibschweißtechnik 2010-2013 Bayerisches Staatsministerium für Wirtschaft, Infrastruktur, Verkehr und Technologie (Forschungsprogramm "BayernFIT") ComBo - Effiziente Fertigungstechnologie fur Composite Boostersegmente 2010-2013 Bundesminist. f. Wirtschaft u. Technologie (Forschungsprogramm "LuFo IV-2") Entwicklung einer luftfahrtspezifischen Carbonfaser und der zugehörigen Halbzeuge 2008-2012 Bayer. Staatsminist. f. Wirtschaft, Infrastruktur, Verkehr, Technologie (Forschungsprogramm "Neue Werkstoffe") Schalldämpferkorrosion - Korrosionsminderung in Schalldämpfern durch Oberflächenbehandlung von Werkstoffen 2008-2011 Bayer. Staatsminist. f. Wirtschaft, Infrastruktur, Verkehr, Technologie (Forschungsprogramm "Neue Werkstoffe") Mehrstufige Verfahren zur Herstellung von CFK-Integralstrukturen 2008-2010 Freistaat Bayern, vertr. d. d. Staatsministerium f. Umwelt, Gesundheit u. Verbraucherschutz (EU 46) Korrosion in Anlagen zur thermischen Abfallbehandlung - Weiterentwicklung und Optimierung einer online Korrosionssonde 2007-2009 Bayerische Forschungsstiftung (FOROXID) Untersuchung von Grenzflächenreaktionen in Metalloxid-Glas- und Metall-Glas-Grenzflächen 2006-2008 Bayer. Staatsminist. f. Wirtschaft, Infrastruktur, Verkehr, Technologie (Forschungsprogramm "Neue Werkstoffe") Optimierung der Grenzfläche Bipolarplatte / leitfähige Beschichtung für serientaugliche PEFC Bipolarplatten 2006-2008 Freistaat Bayern, vertr. d. d. Staatsministerium f. Umwelt, Gesundheit u. Verbraucherschutz (EU 16-19) Korrosion in Anlagen zur thermischen Abfallbehandlung - Entwicklung eines Online-Sensor-Arrays zur Erfassung von Zuständen erhöhter Korrosion
Korrosion in Anlagen zur thermischen Abfallbehandlung - Entwicklung und Betrieb einer online Korrosionssonde2003-2007
