相关论文: Effective Exchange Interactions for Bad Metals and…
We investigate transport in strongly correlated metals. Within dynamical mean-field theory, we calculate the resistivity, thermopower, optical conductivity and thermodynamic properties of a hole-doped Mott insulator. Two well-separated…
The effects of electron-electron correlations on the low-energy electronic structure and their relationship with unconventional superconductivity are central aspects in the research on the iron-based pnictide superconductors. Here we use…
We study the interplay of strong electron correlations and intra-triangle spin exchange at two-thirds filling of the single-orbital Hubbard model on the decorated honeycomb lattice using rotationally invariant slave bosons. We find that the…
The magnon exchange mechanism of superconductivity was developed to explain in a natural way the fact that the superconductivity in $UGe_2$, $ZrZn_2$ and $URhGe$ is confined to the ferromagnetic phase.The order parameter is a spin…
We propose a new mechanism of indirect exchange interaction, which can be responsible for the ferromagnetic ordering in Mn-doped semiconductors (like GaMnAs) at low carrier concentration. The mechanism is based on the interplay of the…
The 122$^{*}$ series of iron-chalcogenide superconductors, for example K$_x$Fe$_{2-y}$Se$_{2}$, only possesses electron Fermi pockets. Their distinctive electronic structure challenges the picture built upon iron pnictide superconductors,…
At a superconductor-ferromagnet (S/F) interface, the F layer can introduce a magnetic exchange field within the S layer, which acts to locally spin split the superconducting density of states. The effect of magnetic exchange fields on…
Because of large spatial separation of the Mn atoms in Heusler alloys the Mn 3d states belonging to different atoms do not overlap considerably. Therefore an indirect exchange interaction between Mn atoms should play a crucial role in the…
We analyze magnetic phases of monolayers of transition metal dichalcogenides that are two-valley materials with electron-electron interactions. The exchange inter-valley scattering makes two-valley systems less stable to the spin…
We study the effects of an orbital magnetic field on the Mott metal-insulator transition in the Hubbard-Hofstadter model. We demonstrate that sufficiently large magnetic fields induce a Mott insulator-to-metal phase transition supporting…
We review some theoretical aspects connected with the interplay of strong electron correlations and vibron phenomena in negative fullerene ions and in solid fulleride conductors, superconductors and insulators. The first part covers…
We argue on the basis of experimental numbers that the B=0 metal-insulator transition in two dimensions, observed in Si-MOSFETs and in other two-dimensional systems, is likely to be due to a few strongly interacting electrons, which also…
A well-known connection between the magnetic susceptibility and the effective exchange parameter is analyzed. It is shown that all current computational schemes use a long-wave approximation which is suitable only for localized moments…
We propose that one of the best grounds for the materials design from the viewpoint of {\it electron correlation} such as ferromagnetism, superconductivity is the atomically controlled nanostructures and heterointerfaces, as theoretically…
It is generally believed that superconductivity only weakly affects the indirect exchange between magnetic impurities. If the distance r between impurities is smaller than than the superconducting coherence length (r < \xi), this exchange…
We study a three-orbital Hubbard-Kanamori model relevant for iron-based superconductors using variational wave functions explicitly including spatial correlations and electron pairing. We span the nonmagnetic sector from filling $n=4$,…
The high-temperature ferromagnet MnBi continues to receive attention as a candidate to replace rare-earth-containing permanent magnets in applications above room temperature. This is due to a high Curie temperature, large magnetic moments,…
Disorder - impurities and defects violating an ideal order - is always present in solids. It can result in interesting and sometimes unexpected effects in multiband superconductors. Especially if the superconductivity is unconventional thus…
We examine the relevance of magneto-elastic coupling to describe the complex magnetic and structural behaviour of the different classes of the iron superconductors. We model the system as a two-dimensional metal whose magnetic excitations…
The effect of an exchange field on electrical transport in thin films of metallic ferromagnetic manganites has been investigated. The exchange field was induced both by direct exchange coupling in a ferromagnet/antiferromagnet multilayer…