Dynamical Mean-Field Theory (DMFT)
The dynamical mean-field theory (DMFT) is a powerful technique to investigate strongly correlated systems. We apply and develop DMFT, in particular in combination with density-functional theory (DFT). We currently focus on methodological developments as well as applications to condensed matter physics and material science. The tool of choice for our activities is the full-potential linearized muffin-tin orbital (FP-LMTO) code RSPt. RSPt includes a fully general DFT+DMFT implementation, with self-consistent cycles over self-energy and charge density. The following solvers are part of RSPt and were developed by our group:
- spin-dependent T-matrix fluctuation-exchange (SPTF)
- Hubbard I approximation (HIA)
- Exact diagonalization (ED)
In RSPt, we also develop methods for extracting interatomic exchange interactions in correlated systems, for performing the analytical continuation of Green's functions and self-energies, and for avoiding the problem of local minima in LDA+U. Currently we are working on methods to calculate X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS) for strongly correlated materials.
Among applications, we have applied our techniques to:
- itinerant ferromagnets Fe, Co and Ni and their compounds
- dilute magnetic semiconductors, as e.g. (Mn,Ga)As
- transition metal oxides, as e.g. NiO and FeO
- rare-earth compounds
- multiferroics, as e.g. BiFeO3
Selected Publications
- Y. O. Kvashnin et al., Physical Review Letters 116, 217202 (2016)
- J. Schött et al., Physical Review B 93, 075104 (2016)
- I. Di Marco et al., Nature Communications 4, 2645 (2013)
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J. M. Wills et al., “Full-Potential Electronic Structure Method”, Springer (2010)