相关论文: Origin of the spin density wave instability in AFe…

We consider electrons on a honeycomb or triangular lattice doped to the saddle point of the bandstructure. We assume system parameters are such that spin density wave (SDW) order emerges below a temperature $T_N$ and investigate the nature…

The normal-state charge transport is studied systematically in high-quality single crystals of BaFe$_2$(As$_{1-x}$P$_x$)$_2$ ($0 \leq x \leq 0.71$). By substituting isovalent P for As, the spin-density-wave (SDW) state is suppressed and the…

Sr$_2$RuO$_4$, an unconventional superconductor, is known to possess an incommensurate spin density wave instability driven by Fermi surface nesting. Here we report a static spin density wave ordering with a commensurate propagation vector…

Neutron scattering shows that non-Fermi-liquid behavior of the heavy-Fermion compound CeNi_2Ge_2 is brought about by development of low-energy spin fluctuations with an energy scale of 0.6 meV. They appear around antiferromagnetic wave…

We use neutron scattering to study the spin and lattice structure on single crystals of SrFe2As2, the parent compound of the FeAs based superconductor (Sr,K)Fe2As2. We find that SrFe2As2 exhibits an abrupt structural phase transitions at…

For the iron-based high $T_c$ superconductor LaFeAsO$_{1-x}$F$_x$, we construct a minimal model, where all of the five Fe $d$ bands turn out to be involved. We then investigate the origin of superconductivity with a five-band random-phase…

We report inelastic neutron scattering (INS) investigations on the bilayer Fe-based superconductor CsCa2Fe4As4F4 above and below its superconducting transition temperature Tc = 28.9 K to investigate the presence of a neutron spin resonance.…

The discovery of alkaline iron selenide $A$Fe$_{1.6+x}$Se$_2$ ($A=$ K, Rb, Cs) superconductors has generated considerable excitement in the condensed matter physics community because superconductivity in these materials may have a different…

We report neutron scattering measurements of cooperative spin excitations in antiferromagnetically ordered BaFe2As2, the parent phase of an iron pnictide superconductor. The data extend up to ~100meV and show that the spin excitation…

An unexpected insensitivity of the Fermi surface to impurity scattering is found in Ru substituted BaFe$_2$As$_2$ from first-principles theory, offering a natural explanation of the unusual resilience of transport and superconductivity to a…

We use inelastic neutron scattering to study temperature and energy dependence of spin excitations in optimally P-doped BaFe2(As0.7P0.3)2 superconductor (Tc = 30 K) throughout the Brillouin zone. In the undoped state, spin waves and…

The parent compounds of iron-based superconductors are magnetically-ordered bad metals, with superconductivity appearing near a putative magnetic quantum critical point. The presence of both Hubbard repulsion and Hund's coupling leads to…

We systematically investigate temperature- and spectrally-dependent optical reflectivity dynamics in AAs$_{2}$Fe$_{2}$, (A=Ba, Sr and Eu), iron-based superconductors parent spin-density-wave (SDW) compounds. Two different relaxation…

To investigate the interplay between charge density wave (CDW) and superconductivity, we performed ultralow-temperature spectroscopic-imaging scanning tunneling microscopy on the cleaved surface of the layered superconductor 2H-NbSe2. We…

We investigate the electronic and other properties of the hypothetical compound LiFeSb in relation to superconducting LiFeAs and FeSe using density functional calculations. The results show that LiFeSb in the LiFeAs structure would be…

We performed inelastic neutron scattering on powder sample of the P-doped iron-based superconductor BaFe2(As0.65P0.35)2 with Tc = 30K, whose superconducting (SC) order parameter is expected to have line nodes. We have observed spin…

The tetragonal heavy-fermion compound CeAuSb$_2$ (space group $P4/nmm$) exhibits incommensurate spin density wave (SDW) order below $T_{N}\approx6.5~K$ with the propagation vector $\mathbf{q}_A = (\delta_A,\delta_A,1/2)$. The application of…

We show that electronic Raman scattering affords a window into the essential properties of the pairing potential $V_{\mathbf{k},\mathbf{k^{\prime}}}$ of iron-based superconductors. In Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ we observe band…

Optical spectroscopy on single crystals of the new iron arsenide superconductor Ba{0.55}K{0.45}Fe2As2 shows that the infrared spectrum consists of two major components: a strong metallic Drude band and a well separated mid infrared…

We investigate the spin fluctuations and the pairing symmetry in A$_{x}$Fe$_{2-y}$Se$_{2}$ by the fluctuation exchange approximation. Besides the on-site interactions, the next-nearest-neighbor antiferromagnetic coupling $J_{2}$ is also…