Related papers: Spin-dependence of Ce $4f$ hybridization in magnet…
Strong angle-dependent intensity variations of the Fermi-level feature are observed in 4d - 4f resonant photoemission spectra of CePd$_3$(111), that reveal the periodicity of the lattice and largest intensity close to the Gamma points of…
High-resolution angle-resolved photoelectron spectroscopy is used to examine the electronic band structure of FeTe$_{0.5}$Se$_{0.5}$ near the Brillouin zone center. A consistent separation of the $\alpha_{1}$ and $\alpha_{2}$ bands is…
Hybridization between $f$ electrons and conduction bands ($c$-$f$ hybridization) is a driving force for many unusual phenomena. To provide insight into it, systematic studies of CeCoIn$_5$ heavy fermion superconductor have been performed by…
Spectra of x-ray absorption and magnetic circular dichroism were measured at M4,5(3d) and L2,3(2p) edges of Ce in multilayers [Ce(1-x)Six/Fe]xn, with x between 0.1 and 0.65. The study uncovers the highly correlated nature of this layered…
A key issue in heavy fermion research is how subtle changes in the hybridization between the 4$f$ (5$f$) and conduction electrons can result in fundamentally different ground states. CeRhIn$_5$ stands out as a particularly notable example:…
We explore the interplay of electron-electron correlations and spin-orbit coupling in the model Fermi liquid Sr2RuO4 using laser-based angle-resolved photoemission spectroscopy. Our precise measurement of the Fermi surface confirms the…
A new mechanism for ferromagnetism in CeRh_3B_2 is proposed on the basis of variational Monte Carlo results. In a one-dimensional Anderson lattice where each 4f electron hybridizes with a ligand orbital between neighboring Ce sites,…
We demonstrate the occurrence of compensated spin configurations in Fe clusters and monolayers on Ru(0001) and Rh(111) by a combination of X-ray magnetic circular dichroism experiments and first-principles calculations. Our results reveal…
We report on results from high-energy spectroscopic measurements on CeFe2, a system of particular interest due to its anomalous ferromagnetism with an unusually low Curie temperature and small magnetization compared to the other rare…
Cerium (Ce)-based heavy-fermion materials have a characteristic double-peak structure (mid-IR peak) in the optical conductivity [$\sigma(\omega)$] spectra originating from the strong conduction ($c$)--$f$ electron hybridization. To clarify…
Hybridization between localized 4$f$ and itinerant 5$d$6$s$ states in heavy fermion compounds is a well-studied phenomenon and commonly captured by the paradigmatic Anderson model. However, the investigation of additional electronic…
Ce 3d-4f resonant angle-resolved photoemission measurements on CeCoGe$_{1.2}$Si$_{0.8}$ and CeCoSi$_{2}$ have been performed to understand the Fermi surface topology as a function of hybridization strength between Ce 4$f$- and conduction…
We propose a minimal model describing magnetic behavior of Fe-based superconductors. The key ingredient of the model is a dynamical mixing of quasi-degenerate spin states of Fe2+ ion by intersite electron hoppings, resulting in an effective…
We present a theoretical study of the dynamical spin susceptibility for the intriguing Fe-based superconductor FeSe, based on a tight-binding model developed to account for the temperature-dependent band structure in this system. The model…
Using spin density functional theory we have carried out a comparative study of chemical bonding and magnetism in Fe_4N, Fe_3N and Fe_2N. All of these compounds form close packed Fe lattices, while N occupies octahedral interstitial…
$Fe_3O_4$ is a mixed-valence strongly correlated transition metal oxide which displays the intriguing metal to insulator Verwey transition. Here we investigate the electronic and magnetic structure of $Fe_3O_4$ by a unique combination of…
We present a simultaneous investigation of coherent spin dynamics in both localized and itinerant carriers in Fe/GaAs heterostructures using ultrafast and spin-resolved pump-probe spectroscopy. We find that for excitation densities that…
Being homologue to the new, Fe-based type of high-temperature superconductors, CeFePO exhibits magnetism, Kondo and heavy-fermion phenomena. We experimentally studied the electronic structure of CeFePO by means of angle-resolved…
Using \emph{ab initio} linear response techniques we calculate spin wave spectra in K$_{2}$Fe$_{4+x}$Se$_{5}$, and find it to be in excellent agreement with a recent experiment. The spectrum can be alternatively described rather well by…
We clarify the macroscopic symmetry and microscopic model-parameter conditions for emergence of spin-split electronic band structure in collinear antiferromagnets without atomic spin-orbit coupling. By using the microscopic multipole…