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| Research group Prof. Dr. P. Kratzer 
German
Research group Research Teaching Various |
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| home » research topics | ||||||||
| Ab initio simulations are employed to investigate materials at the basis of modern energy technology, such as thermoelectric converters and solar cells, and non-volatile memory for computers | ||||||||
| theory of thermoelectric properties of self-assembled nanocrystals in semiconductor matrix, | ||||||||
| segregation and ordering in ternary metal or semiconductor alloys, | ||||||||
| atomic-scale modeling of semiconductor nanowire growth | ||||||||
| theory of non-adiabatic electronic excitations at surfaces | ||||||||
| theory of vibrational damping in adsorbates and thin surface layers | ||||||||
| multi-scale modeling of materials with optimized transport properties | ||||||||
| Following demands for materials with peculiar transport properties, e.g. in photovoltaic, spintronic or thermoelectric applications, there is a need for materials modeling at the quantum-mechanical level. We aim at developing both the conceptual basis and the software tools for interfacing density-functional calculations with scale-bridging simulation tools to establish the interrelation between the macroscopic transport properties and the atomic structure of materials. For examples, magnetic alloys for spintronics display a high level of spin polarization only if highly ordered. Ab initio thermodynamics needs to be combined with a cluster expansion of interactions in disordered systems to screen the huge configuration space for materials with novel properties. Nanostructured semiconductors, e.g. with a regular arrangement of nano-scale inclusions ("quantum dot crystals"), hold the promise of high thermoelectric figure of merit. Simulating their geometry-controlled properties requires the development of multi-scale simulation tools where the lowest scale involves a quantum treatment of systems with up to a million atoms. | ||||||||
| Examples | ||||||||
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Heusler Alloy (ferromagnetic half metal) |
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manganese silicide layer on silicon |
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electronic wavefunction of a Si27 cluster |
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InAs quantum dot on gallium arsenide |
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