Related papers: Correlation effects in the iron pnictides
In this paper, instabilities of the isotropic metallic phase in iron pnictides are investigated. The relevant quartic fermionic interaction terms in the model are identified using phase space arguments. Using the functional integral…
We present a polarization resolved study of the low energy band structure in the optimally doped iron pnictide superconductor Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ (T$_c$=37K) using angle resolved photoemission spectroscopy.…
Motivated by the recent angle-resolved photoemission spectroscopy (ARPES) on FeSe and iron pnictide families of iron-based superconductors, we have studied the orbital nematic order and its interplay with antiferromagnetism within the…
We present a way of partly reincorporate the effects of the localized bonding electrons on the dynamics of their itinerant counterparts in Hubbard-like Hamiltonians. This is done by relaxing the constraint that the former should be entirely…
Many of the iron pnictides have strongly anisotropic normal-state characteristics, important for the exotic magnetic and superconducting behavior these materials exhibit. Yet, the origin of the observed anisotropy is unclear. Electronically…
The metal-insulator transition (MIT) remains among the most thoroughly studied phenomena in solid state physics, but the complexity of the phenomena, which usually involves cooperation of many degrees of freedom including orbitals,…
To investigate the superconducting properties of iron pnictides we prepared planar hybrid SNS' junctions in thin film technology with a pnictide base electrode, a gold barrier layer and a lead counter electrode. Our design allows…
A number of methods are discussed which may serve for a treatment of electron correlations in solids. When the electron correlations are relatively weak like in semiconductors or a number of ionic crystals one may start from a…
Emergence of novel quantum ground states in correlated electron systems with strong spin-orbit coupling has been a recent subject of intensive studies. While it has been realized that spin-orbit coupling can provide non-trivial band…
The phenomenology of iron-pnictides superconductors can be explained in the framework of a three bands s\pm wave Eliashberg theory with only two free parameters plus a feedback effect i.e. the effect of the condensate on the…
Analyzing the motion of low--spin $(s=1/2)$ holes in a high--spin $(S=1)$ background, we derive a sort of generalized t--J Hamiltonian for the $\rm NiO_2$ planes of Sr--doped nickelates. In addition to the rather complex carrier--spin and…
We study the effects of electron correlation on transport through an interacting region connected to multi-mode leads based on the perturbation expansion with respect to the inter-electron interaction. At zero temperature the conductance…
The notion of strong electronic correlations arose in the context of $d$-metal oxides such as NiO but can be exemplified on systems as simple as the H$_2$ molecule. Here we shed light on correlation effects on B$_6^{2-}$ clusters as found…
We describe the correlated electronic structure of a prototype Fe-pnictide superconductor, $SmO_{1-x}F_{x}FeAs$, using LDA+DMFT. Strong, multi-orbital electronic correlations generate a low-energy pseudogap in the undistorted phase, giving…
The unusual features of topological semimetals arise from its nontrivial band structure. The impact of strong electron correlations on the topological states remains largely unexplored in real materials. Here, we report the magnetotransport…
We consider superconductivity in a system with $N$ Fermi surfaces, including intraband and interband effective electron-electron interactions. The effective interaction is described by an $N \times N$ matrix whose elements are assumed to be…
In a magnetically driven electronic nematic state, an externally applied uniaxial strain rounds the nematic transition and increases the magnetic transition temperature. We study both effects in a simple classical model of the…
Theoretical descriptions of the spectrum of electronic excitations in real metals have not yet reached a fully predictive, "first-principles" stage. In this paper we begin by presenting brief highlights of recent progress made in the…
We report a $^{13}$C-NMR study on the ambient-pressure metallic phase of the layered organic conductor $\theta$-(BEDT-TTF)$_{2}$I$_{3}$ [BEDT-TTF: bisethylenedithio-tetrathiafulvalene], which is expected to connect the physics of correlated…
The layered molecular conductors $\kappa$-(BEDT-TTF)$_2$X are a perfect experimental platform for studying the physics of the Mott transition and related exotic electronic states. In these materials, the subtle balance between various…