Learn More
c © 2002 by John von Neumann Institute for Computing Permission to make digital or hard copies of portions of this work for personal or classroom use is granted provided that the copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise requires prior(More)
This dissertation is concerned with the theoretical investigation of the electronic and magnetic properties of 4f systems with film geometry. The presented theory is based on the s-f model which features an intra-atomic exchange between a system of localized magnetic moments and the conduction electrons. The model is investigated for the special case of(More)
The complexity of strongly correlated electron physics in vanadium dioxide is exemplified as its rich phase diagrams of all kinds, which in turn shed light on the mechanisms behind its various phase transitions. In this work, we map out the hydrostatic pressure-temperature phase diagram of vanadium dioxide nanobeams by independently varying pressure and(More)
To compare the metal-insulator transitions (MITs) of VO2 and V2O3 we analyze the relations between the structural and electronic properties of the vanadium Magnéli phases. These materials set up the homologous series VnO2n−1 (3 ≤ n ≤ 9) and have crystal structures comprising typical dioxide-like and sesquioxidelike regions. As the MITs of the vanadium(More)
The stability of ferr* and antiferrornagnetism in 4f-systems with valence fluctuations between magnetic and nonmagnetic configurations is investigated in the framework of an extended s-f model. Intensifying the electronic transitions by varying the 5 f hybridization or the 4f-level position tends to quench the local magnetic 4f-moments and, competingly, the(More)
Results of atomic-scale simulations are presented including thermal conductivity, elastic moduli, diffusion, and adhesion. This type of simulations is most conveniently performed with the MedeA<sup>&#x00AE;</sup> computational environment, which comprises experimental structure databases together with building tools to construct models of complex solids,(More)