Related papers: Isotope effect in impure high T_c superconductors
The results of the Fe isotope effect (Fe-IE) on the transition temperature $T_c$ obtained up to date in various Fe-based high temperature superconductors are summarized and reanalyzed by following the approach developed in [Phys. Rev. B 82,…
Neutron scattering experiments have been carried out to explore Ni-impurity effects on static spin correlations in La2-xSrxCuO4 (LSCO) in the vicinity of the superconductor-insulator boundary where both parallel and diagonal spin-density…
Superconductivity in high-Tc cuprates is unconventional and there is a growing acceptance that carrier pairing in these strongly correlated electronic materials is mediated mainly by bosons of electronic origin rather than the phonons.…
We examine the isotope effect of superconductivity in systems with coexisting interactions of phonon and nonphonon mechanisms in addition to the direct Coulomb interaction. The interaction mediated by the spin fluctuations is discussed as…
The effect of a homogeneous magnetic field and nonmagnetic impurities on the critical temperature of an anisotropic superconductor has been investigated. The role of these pair-breakers in relation to the anisotropy of the order parameter…
The in-plane infrared response of the high-Tc cuprate superconductors was studied using the spin-fermion model, where charged quasiparticles of the copper-oxygen planes are coupled to spin fluctuations. First, we analyzed structures of the…
Precise neutron-scattering experiments on La$_{1.88-y}$Sr$_{0.12+y}$Cu$_{0.99}$R$_{0.01}$O$_4$ ($y$=0 for R=Cu, Zn and $y$=0.01 for R=Ga, Fe) were performed to examine the stability of stripe order in cuprate oxides through impurity…
In materials with strong local Coulomb interactions, simple defects such as atomic substitutions strongly affect both macroscopic and local properties of the system. A nonmagnetic impurity, for instance, is seen to induce magnetism nearby.…
Close to a zero temperature transition between ordered and disordered electronic phases, quantum fluctuations can lead to a strong enhancement of the electron mass and to the emergence of competing phases such as superconductivity. A…
The high-T_c cuprate superconductors are now believed to be intrinsically inhomogeneous. We develop a theory to describe how this inhomogeneity affects the intermodulation coefficient of such a material. We show that the continuum equations…
In the theory of dilute magnetic impurities in superconductors, the effect of all impurity spin-components is expressed via a single magnetic scattering rate $\Gamma_\mathrm{m}$. In a more realistic setting, magnetic impurities are…
The magnetic field and temperature dependence of the electronic specific heat $C_{\rm el}$ have been systematically investigated in $\rm La_{2-{\it x}}Sr_{\it x}Cu_{1-{\it y}}Ni_{\it y}O_4$ (LSCNO) in order to study Ni-impurity effects on…
We consider the effect of isotropic impurity scattering on the exotic superconducting states that arise from the usual BCS mechanism in substances of cubic and hexagonal symmetry where the Fermi surface contains inequivalent but degenerate…
Tunneling conductance spectra between a normal metal / d-wave superconductor junction under the presence of bulk impurities in the superconductor are studied. The quasiclassical theory has been applied to calculate the spatial variation of…
The upper critical field $H_{c2} $, the field $H_{c3}$ for nucleation of the surface superconductivity, and the thermodynamic $H_c $ are evaluated within the weak-coupling theory for the isotropic s-wave case and arbitrary transport and…
We consider superconductivity in the presence of impurities in a two-band model suited for the description of iron-based superconductors. We analyze the effect of interband scattering processes on superconductivity, allowing for orbital,…
We investigate the single normal impurity effect in a superconductor by the holographic method. When the size of impurity is much smaller than the host superconductor, we can reproduce the Anderson theorem, which states that a conventional…
A reentrant temperature dependence of the thermoresistivity $\rho_{\mathrm{xx}}(T)$ between an onset local superconducting ordering temperature $T_\mathrm{loc}^\mathrm{onset}$ and a global superconducting transition at…
We have systematically investigated the effect of oxygen nonstoichiometry in a nominally undoped superconductor T'-(La,Y)2CuO4+y. In the experiments, the reduction condition was changed after the sample growth by MBE. The superconductivity…
Chiral superconductors exhibit novel transport properties that depend on the topology of the order parameter, topology of the Fermi surface, the spectrum of bulk and edge Fermionic excitations, and the structure of the impurity potential.…