Related papers: Disorder effects and current percolation in FeAs b…
Predicting the change of performance of superconductors under neutron radiation is indispensable for designing compact fusion devices. The favorable enhancement of the critical current caused by flux pinning is separated from the degrading…
We present results of a numerical mean field treatment of interacting spins and carriers in doped diluted magnetic semiconductors, which takes into account the positional disorder present in these alloy systems. Disorder is found to enhance…
We present a \asnmr Nuclear Magnetic Resonance (NMR) and resistivity study of the effect of 5.5 MeV proton irradiation on the optimal electron doped ($x=$ 0.068) and overdoped ($x=$ 0.107) Ba(Fe$_{1-x}$Rh$_x$)$_2$As$_2$ iron based…
Multiharmonic ac-magnetic susceptibility \ch11,\chi2,chi3, of neutron irradiated Li-doped YBa2Cu3O7-x has revealed a nonmonotonic dependence of all harmonics on the neutron fluence. The irradiation has a strongly depressive influence on the…
A detailed account of the local atomic structure and disorder at 5~K across the phase diagram of the high temperature superconductor K$_x$Fe$_{2-y}$Se$_{2-z}$S$_z$ $(0 \leq z \leq 2)$ is obtained from neutron total scattering and associated…
We examine the effects of disorder on striped phases in high-temperature superconductors and related materials. In the presence of quenched disorder, pinning by the atomic lattice - which might give rise to commensuration effects - is…
We investigate patterns of critical current as a function of perpendicular and in-plane magnetic fields in superconductor-semiconductor-superconductor (SNS) junctions based on InAs/InGaAs heterostructures with an epitaxial Al layer. This…
Superconducting and normal state transport properties in iron pnictides are sensitive to disorder and impurity scattering. By investigation of Ba(Fe1-xCox)2As2 thin films with varying Co concentration, we demonstrate that in the dirty limit…
We investigate the influence of weak disorder on the fluctuation driven first order transition found in a p-wave superconductor. The flow equations for the disorder averaged effective theory is derived in an $4-\epsilon$ expansion. The…
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…
Effects of superconducting fluctuation (SCF) on thermodynamic properties of electron systems in the so-called BCS-BEC-crossover regime are studied. As the attractive interaction between electrons becomes stronger upon approaching the…
We report a direct current transport study of the local intergrain connections in a polycrystalline SmFeAsO0.85 (Sm1111) bulk, for which we earlier estimated significant intergranular critical current density Jc. Our combined low…
Irradiation with Pb ions was used to study the effect of disorder on the in-plane London penetration depth, $\lambda(T)$, in single crystals of Ba(Fe$_{1-x}$T$_x$)$_2$As$_2$ (T=Co, Ni). An increase of the irradiation dose results in a…
In this letter we present the effect of neutron irradiation up to fluences of 3.9 1019 n/cm2 on the superconducting properties of MgB2. In order to obtain a disorder structure homogeneously distributed, the experiment was carried out on…
We calculate the degree of flux pinning by defects in model high-temperature superconductors (HTSC's). The HTSC is modeled as a three-dimensional network of resistively-shunted Josephson junctions in an external magnetic field,…
Mastery of order-disorder processes in highly non-equilibrium nanostructured oxides has significant implications for the development of emerging energy technologies. However, we are presently limited in our ability to quantify and harness…
Two iron-chalcogenide superconductors Li(x)[C5H5N](y)Fe(2-z)Se2 and Cs(x)Fe(2-z)Se2 in the as-prepared and annealed state have been investigated by means of the Moessbauer spectroscopy versus temperature. Multi-component spectra are…
We present a comprehensive overview of vortex pinning in single crystals of the isovalently substituted iron-based superconductor BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$, a material that qualifies as an archetypical clean superconductor,…
Low-temperature variable-energy electron irradiation was used to induce non-magnetic disorder in a single crystal of hole-doped iron-based superconductor, Ba$_{1-x}$K$_x$Fe$_2$As$_2$, $x=$0.80. To avoid systematic errors, the beam energy…
We describe the effects of disorder on the critical temperature of s-wave superfluids from the BCS to the BEC regime, with direct application to ultracold Fermi atoms. In the BCS regime the pair breaking and phase coherence temperature…