相关论文: Theoretical study on the correlation between the s…
The multiband nature of iron pnictides gives rise to a rich temperature-doping phase diagram of competing orders and a plethora of collective phenomena. At low dopings, the tetragonal-to-orthorhombic structural transition is closely…
Characterizing magnetic fluctuations is one of the keys to understanding the origin of superconductivity in the spin-triplet superconductor UTe$_2$ which exhibits two superconducting (SC) phases (SC1 and SC2) under pressure: SC1 where a…
Strong interplay of spin and charge/orbital degrees of freedom is the fundamental characteristic of the iron-based superconductors (FeSCs), which leads to the emergence of a nematic state as a rule in the vicinity of the antiferromagnetic…
Muon-spin rotation experiments were performed on the pnictide high temperature superconductor SmFeAsO$_{1-x}$F$_{x}$ with x=0.18 and 0.3. We observed an unusual enhancement of slow spin fluctuations in the vicinity of the superconducting…
We investigate theoretically the superconducting state of the undoped Fe-based superconductor ThFeAsN. Using input from $ab~initio$ calculations, we solve the Fermi-surface based, multichannel Eliashberg equations for Cooper-pair formation…
The electron-doped high-transition-temperature (T_c) iron-based pnictide superconductor LaFeAsO_{1-x}H_x has a unique phase diagram: superconducting (SC) double domes are sandwiched by antiferromagnetic phases at ambient pressure and they…
We theoretically study the spin fluctuation and superconductivity in La1111 and Sm1111 iron-based superconductors for a wide range of electron doping. When we take into account the band structure variation by electron doping, the hole Fermi…
The phase diagram of LaFeAs$_{1-x}$P$_x$O system has been extensively studied through hole- and electron-doping as well as As/P-substitution. It has been revealed that there are three different superconducting phases with different Fermi…
The quantum critical Antiferromagnetic (AFM) fluctuation spectra measured by inelastic neutron scattering recently in two heavy fermion superconductors are used together with their other measured properties to calculate their D-wave…
We report systematic 31P-NMR study on iron (Fe)-based superconductors SrFe2(As_{1-x}P_{x})2 (Sr122AsP), in which a superconducting (SC) transition temperature Tc at x=0.35 increases from Tc=26 K up to 33 K by annealing an as-grown…
It is shown that anomalous properties of UGe_2 can be understood in a unified way on the basis of a single assumption that the superconductivity is mediated by the coupled SDW and CDW fluctuations induced by the imperfect nesting of the…
The pairing mechanism in iron-based superconductors is the subject of ongoing debate. Proximity to an antiferromagnetic phase suggests that pairing is mediated by spin fluctuations, but orbital fluctuations have also been invoked. The…
Using neutron scattering we have determined the magnetic structure and fluctuations in the YBa2Cu3O6.35 superconductor (Tc=18 K). The long-range ordered collinear spins of the insulating antiferromagnet are replaced by a commensurate…
We propose orbital fluctuations in a multi-band ground state as the superconducting pairing mechanism in the new iron-based materials. We develop a general SU(4) theoretical framework for studying a two-orbital model and discuss a number of…
We have measured magnetization at high pressure in the uranium ferromagnetic superconductor UGe$_2$ and analyzed the magnetic data using Takahashi's spin fluctuation theory. There is a peak in the pressure dependence of the width of the…
Elucidating the microscopic origin of nematic order in iron-based superconducting materials is important because the interactions that drive nematic order may also mediate the Cooper pairing. Nematic order breaks fourfold rotational…
Superconductivity mediated by spin fluctuations in weak and nearly ferromagnetic metals is studied close to the zero-temperature magnetic transition. We solve analytically the Eliashberg equations for p-wave pairing and obtain the normal…
Superconductivity is a quantum phenomenon caused by bound pairs of electrons. In diverse families of strongly correlated electron systems, the electron pairs are not bound together by phonon exchange but instead by some other kind of…
We propose a model for high-T$_{c}$ superconductors, valid for $0\leq\delta\leq\delta_{SC}$, that includes both the spin fluctuations of the Cu$^{++}$ magnetic ions and of the O$^{--}$ doped holes. Spin-charge separation is taken into…
The relationship between antiferromagnetic (AFM) spin fluctuations (SF), nematic fluctuations, and superconductivity (SC) has been central to understanding the pairing mechanism in iron-based superconductors (IBSCs). Iron chalcogenides,…