Related papers: Enhanced superfluid density on twin boundaries in …
Macroscopic current uniformity in a (Ba,K)Fe2As2 bulk sample produced by a process that demonstrated high trapped magnetic fields was evaluated through a comparative experimental and modeling approach. The bulk sample, with a well-defined…
Magnetization and its relaxation have been measured in $Ba(Fe_{1-x}Co_x)_2As_2$ single crystals at various doping levels ranging fromvery underdoped to very overdoped regimes. Sizable magnetization relaxation rate has been observed in all…
Using muon spin rotation (muSR) we investigated the magnetic and superconducting properties of a series of Ba(Fe1-xCox)2As2 single crystals with 0 =< x =< 0.15. Our study details how the antiferromagnetic order is suppressed upon Co…
High-Tc superconducting materials (HTSC) have anomalous properties such as the pseudo-gap or spin-gap etc., in Hall coefficient, 1/T1T and the density of states etc. First including effects of strong on-site repulsion between d-electrons at…
Local magnetic measurements are used to quantitatively characterize heterogeneity and flux line pinning in PrFeAsO_1-y and NdFeAs(O,F) superconducting single crystals. In spite of spatial fluctuations of the critical current density on the…
In the temperature-concentration phase diagram of most iron-based superconductors, antiferromagnetic order is gradually suppressed to zero at a critical point, and a dome of superconductivity forms around that point. The nature of the…
We address the question of probing the supercurrents in superconducting (SC) samples on a local scale by performing Scanning Tunneling Spectroscopy (STS) experiments with a SC tip. In this configuration, we show that the tunneling…
Modern Superconducting QUantum Interference Devices (SQUIDs) are commonly fabricated from either Al or Nb electrodes, with an in-situ oxidation process to create a weak link between them. However, common problems of such planar nano- and…
We have studied the interplay of magnetism and superconductivity in LaFeAsO$_{1-x}$F$_x$ and Ca(Fe$_{1-x}$Co$_x$)$_2$As$_2$. While antiferromagnetic spin density wave formation is suppressed and superconductivity evolves, all samples show a…
The flux flow resistivity associated with purely viscous motion of vortices in high-quality MgB_2 was measured by microwave surface impedance. Flux flow resistivity exhibits unusual field dependence with strong enhancement at low field,…
We investigated experimentally the transport properties of a superconducting cross-shaped aluminium microbridge fabricated on top of ferromagnetic BaFe12O19 single crystal. It was demonstrated that a one-dimensional domain structure in the…
The relation between the spin-density-wave (SDW) and superconducting order is a central topic in current research on the FeAs-based high Tc superconductors. Conflicting results exist in the LaFeAs(O,F)-class of materials, for which whether…
Superconducting quantum interference devices (SQUIDs) and related circuits made of aluminum are known to display $1/\omega$ flux noise, where $\omega$ is frequency. A recent experiment showed that the application of an external magnetic…
Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions through which they communicate by Josephson tunneling to establish the macroscopic superconducting state [1]. Although…
The magnetic response is a state-defining property of superconductors. The magnetic flux penetrates type-II bulk superconductors by forming quantum vortices when the enclosed magnetic flux is equal to the magnetic flux quantum. The flux…
The presence of a small concentration of in-plane Fe dopants in La$_{1.87}$Sr$_{0.13}$Cu$_{0.99}$Fe$_{0.01}$O$_4$ is known to enhance stripe-like spin and charge density wave (SDW and CDW) order, and suppress the superconducting $T_c$.…
The spontaneous expulsion of applied magnetic field, the Meissner effect, is a defining feature of superconductors; in Type-II superconductors above the lower critical field, this screening takes the form of a lattice of magnetic flux…
We investigate Cu-doped Ba(Fe$_{1-x}$Cu$_x$)$_2$As$_2$ with transport, magnetic susceptibility, and elastic neutron scattering measurements. In the heavily Cu-doped regime where long-range stripe-type antiferromagnetic order in…
We study theoretically the effect of the fermion and boson densities on the superconductivity transition critical temperature $(T_c)$ of a two dimensional electron gas (2DEG), where superconductivity is mediated by a Bose-Einstein…
Ferrofluids are a synthetic magnetic colloid consisting of magnetized nanoparticles surrounded by a repulsive surfactant layer. When subjected to an external magnetic field the ferrofluid acquires a macroscopic magnetization density which…