相关论文: Dimer Impurity Scattering, "Reconstructed" Nesting…
We study impurity-induced magnetic order within a five-band Hubbard model relevant to the normal paramagnetic phase of iron-based superconductors. The existence of the local magnetic order is explained in terms of an impurity-enhancement of…
Orbital-ordering instability arising due to the intrapocket nesting is investigated for the tight-binding models of pnictides in the presence of orbital-lattice coupling. The incommensurate instabilities with small momentum, which may play…
We report a $^{23}$Na and $^{75}$As nuclear magnetic resonance (NMR) investigation of Na$_{x}$FeAs series ($x=1$, 0.9, 0.8) exhibiting a spin-density wave (SDW) order below $T_{\rm SDW}=45$, 50 and 43 K for $x=1$, 0.9, 0.8, respectively,…
The impurity is inherently manifest in cuprate superconductors, as cation substitution or intercalation is necessary for the introduction of charge carriers, and its influence on the electronic state is at the heart of a great debate in…
Experiments on underdoped cuprate superconductors suggest an intricate relation between the normal-state Nernst effect and stripe order: The Nernst signal appears enhanced near 1/8 hole doping and its onset temperature scales with the…
Hidden spin-density waves (hSDW) with Neel ordering vector (pi,pi) have been proposed recently as parent groundstates to electron-doped iron-selenide superconductors. Doping such groundstates can result in visible electron-type Fermi…
A single impurity problem is investigated for multiband s-wave superconductors with different sign order parameters (+-s-wave superconductors) suggested in Fe-pnictide superconductors. Not only intraband but also interband scattering is…
We present a mean-field theoretical study on the effect of a single non-magnetic impurity in quasi-one dimensional unconventional density wave. The local scattering potential is treated within the self-consistent $T$-matrix approximation.…
We survey recent experimental results including quantum oscillations and complementary measurements probing the electronic structure of underdoped cuprates, and theoretical proposals to explain them. We discuss quantum oscillations measured…
We study impurity bound states and impurity-induced order in the superconducting state of LiFeAs within a realistic five-band model based on the band structure and impurity potentials obtained from density functional theory (DFT). In…
We analyze spin density wave (SDW) order in iron-based superconductors and electronic structure in the SDW phase. We consider an itinerant model for Fe-pnictides with two hole bands centered at $(0,0)$ and two electron bands centered at…
Shortly after the discovery of topological band insulators, topological Kondo insulators (TKIs) have also been theoretically predicted. The latter has ignited revival interest in the properties of Kondo insulators. Currently, the…
We study the local density of states around potential scatterers in d-wave superconductors, and show that quantum interference between impurity states is not negligible for experimentally relevant impurity concentrations. The two impurity…
A key to understand how electrons behave in crystalline solids is the band structure that connects the energy of electron waves to their wavenumber (k). Even in the phase of matter with only short-range order (liquid or amorphous solid),…
The kagome superconductor family AV3Sb5 (A=Cs, K, Rb) emerged as an exciting platform to study exotic Fermi surface instabilities. Here we use spectroscopic-imaging scanning tunneling microscopy (SI-STM) and angle-resolved photoemission…
The possibility of realizing pair density wave (PDW) phases, in which Cooper pairs have a finite momentum, presents an interesting challenge that has been studied in a wide variety of systems. In conventional superconductors, this is only…
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…
Incommensurate (IC) charge-order (CO) and spin density wave (SDW) order in electron doped SrMn1-xWxO3-{\delta} (x= 0.08 to 0.1875) have been studied using neutron diffraction.The study highlights the drastic effect of electron doping on the…
High-temperature superconductivity occurs as copper oxides are chemically tuned to have a carrier concentration intermediate between their metallic state at high doping and their insulating state at zero doping. The underlying evolution of…
We examine the appearance of the experimentally-observed stripe spin-density-wave magnetic order in five different orbital models of the iron pnictide parent compounds. A restricted mean-field ansatz is used to determine the magnetic phase…