Related papers: First-principles perspective on magnetic second so…
Spin fluctuations have a substantial influence on the electron and lattice behaviors in magnetic materials, which, however, is difficult to be tracked properly by prevalent first-principles methods. We propose a versatile self-adaptive…
We calculated the structural, electronic and magnetic properties of FeSe within density-functional theory at the generalized gradient approximation level. First, we studied how the bandwidth of the d-bands at the Fermi energy are…
Motivated by the premise that superconductivity in iron-based superconductors is unconventional and mediated by spin fluctuations, an intense research effort has been focused on characterizing the spin excitation spectrum in the…
A counter-intuitive enhancement of quantum fluctuation with larger spins, together with a few novel physical phenomena, is discovered in studying the recently observed emergent magnetism in high-temperature superconductor FeSe under…
An investigation of possibilities for superconductivity mediated by spin fluctuations in some elementary metals is motivated by the recent discovery of superconductivity in the hcp high-pressure phase of iron. The electronic structure, the…
We report neutron scattering studies on static magnetic orders and spin excitations in the Fe-based chalcogenide system Fe$_{1+\delta}$Se$_{x}$Te$_{1-x}$ with different Fe and Se compositions. Short-range static magnetic order with the…
Polarized Raman-scattering spectra of superconducting, single-crystalline FeSe evidence pronounced phonon anomalies with temperature reduction. A large 6.5% hardening of the B_1g(Fe) phonon mode is attributed to the suppression of local…
Electronic structure calculations are used to analyze the electronic and magnetic properties in {K$_{2}$Fe$_{4+x}$Se$_{5}$}. Fe atoms can be divided into two distinct groups. The $x{=}0$ (parent) compound forms an insulating, collinear,…
Based on the effective four-band model we analyze the spin response in the normal and superconducting states of the Fe-pnictide superconductors. While the normal state spin excitations are dominated by the continuum of the interorbital…
The nature of the superconducting state in the recently discovered Fe-based superconductors1-3 is the subject of intense scrutiny. Neutron scattering investigations have already elucidated a strong correlation between magnetism and…
Magnetic spin fluctuations is one candidate to produce the bosonic modes that mediate the superconductivity in the ferrous superconductors. Up until now, all of the LaOFeAs and BaFe2As2 structure types have simple commensurate magnetic…
Spin-disorder resistivity of Fe and Ni and its temperature dependence are analyzed using noncollinear density functional calculations within the supercell method. Different models of thermal spin disorder are considered, including the…
Magnetic order is usually associated with well-defined magnon excitations. Exotic magnetic fluctuations with fractional, topological or multipolar character, have been proposed for radically different forms of magnetic matter such as…
Using linear-response density-functional theory, we obtain the magnetic interactions in the several iron pnictides. The ground state has been found to be non-collinear in FeSe, with a large continuum of nearly degenerate states lying very…
Motivated by recent neutron scattering experiments in Fe-based superconductors, we study how the magnetic resonance in the superconducting state is affected by the simultaneous presence of either static or fluctuating magnetic orders using…
Nematicity and magnetism are two key features in Fe-based superconductors, and their interplay is one of the most important unsolved problems. In FeSe, the magnetic order is absent below the structural transition temperature $T_{str}=90$K,…
By analyzing Fe-Ni-B compositional diagram we predict an energetically and dynamically stable FeNiB2 compound. This system belongs to the class of highly responsive state of material, as it is very sensitive to the external perturbations.…
Polarized inelastic neutron scattering experiments were performed to study magnetic excitations in the normal and superconducting phases of Co-underdoped BaFe$_2$As$_2$, which exhibits coexistence of antiferromagnetic order and…
The spin resonance observed in the inelastic neutron scattering data on Fe-based superconductors has played a prominent role in the quest for determining the symmetry of the order parameter in these compounds. Most theoretical studies of…
The interplay of orbital and spin degrees of freedom is the fundamental characteristic in numerous condensed matter phenomena, including high temperature superconductivity, quantum spin liquids, and topological semimetals. In iron-based…