Related papers: Vortex lattice disorder in YBCO probed using Beta-…
The Abricosov vortex and bundles dynamics was experimentally investigated in Earth's magnetic field range. Isothermal relaxation features in YBCO single crystal samples with strong pinning centers were studied for different sample-field…
We report magnetoresistance measurements through Nb films having a periodic thickness modulation. The cylinder shaped large-thickness regions of the sample, which form a square lattice, act as repulsive centers for the superconducting…
We use Monte Carlo simulations of the 3D uniformly frustrated XY model, with uncorrelated quenched randomness in the in-plane couplings, to model the effect of random point pins on the vortex line phases of a type II superconductor. We map…
Vortex breaking has been traditionally studied for nonuniform critical current densities, although it may also appear due to nonuniform pinning force distributions. In this article we study the case of a…
Trapped low magnetic flux dynamics including local ones are investigated in YBCO single crystals in the strong thermal fluctuations domain near the superconducting phase transition temperatures. The essential difference from…
Combined synchrotron angle-dispersive powder diffraction and micro-Raman spectroscopy are used to investigate the pressure-induced lattice instabilities that are accompanied by T$_{\rm c}$ anomalies in YBa$_{\rm 2}$Cu$_{\rm 4}$O$_{\rm 8}$,…
We demonstrate a geometrical effect on the depinning line (DL) of the flux line lattice of the Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ high-T$_c$ superconductor (HTSC) micrometer ring. The DL shifts to notably lower temperatures in…
The superconducting state of an optimally doped single crystal of Ba(Fe$_{0.93}$Co$_{0.07}$)$_2$As$_2$ was investigated by $^{75}$As NMR in high magnetic fields from 6.4 T to 28 T. It was found that the Knight shift is least affected by…
We present a magnetization study of low density YBCO ceramics carried out in magnetic fields 0.5 Oe < H < 50 kOe. It was demonstrated that superconducting links between grains may be completely suppressed either by a magnetic field of the…
In type-I superconductors, zero electrical resistivity and perfect diamagnetism define two fundamental criteria for superconducting behavior. In contrast, type-II superconductors exhibit more complex mixed state physics, where magnetic flux…
We report the studies of detailed magnetic relaxation and isothermal magnetization measurements in the vortex state of the 112-type iron-pnictide Ca$_{0.82}$La$_{0.18}$Fe$_{0.96}$Ni$_{0.04}$As$_2$ superconductor with $T_c$ $\sim$ 22 K. In…
Alternating (AC) magnetic fields can induce not only an alternating magnetization in materials, but also an alternating temperature via the magnetocaloric effect. The latter effect is typically neglected when performing AC susceptibility…
A scanning SQUID microscope was used to image vortex trapping as a function of the magnetic induction during cooling in thin-film YBCO strips for strip widths W from 2 to 50 um. We found that vortices were excluded from the strips when the…
We use Monte Carlo simulations to study the finite temperature behavior of vortices in the XY- model for tangent vector order on curved backgrounds. Contrary to naive expectations, we show that the underlying geometry does not affect the…
A micron sized single crystal of the superconductor BSCCO was studied using silicon mechanical micro-oscillators at various tilt angles of the dc magnetic field with respect to the c axis of the sample. Different phases of the vortex matter…
SQUID magnetization measurements in oriented powders of Y$_{1-x}$Ca$_{x}$Ba$% _{2}$Cu$_{3}$O$_{y}$, with $x$ ranging from 0 to 0.2, for $y\approx 6.1$ and $y\approx 6.97$, have been performed in order to study the doping dependence of the…
A comprehensive inelastic neutron scattering study of magnetic excitations in the near-optimally doped high-temperature superconductor ${\rm YBa_{2}Cu_{3}O_{6.85}}$ is presented. The spin correlations in the normal state are commensurate…
We study the mixed state in an extreme type-II lattice d-wave superconductor in the regime of intermediate magnetic fields H_{c1} << H << H_{c2}. We analyze the low energy spectrum of the problem dominated by nodal Dirac-like quasiparticles…
In a recent paper, Matl et al present a high-frequency study of the complex resistivity of a pinned vortex lattice in YBaCuO . They focus on the inductive-to-resistive transition which is investigated as a function of temperature at a…
Low-angle grain boundaries with misorientation angles theta < 5 degrees in optimally doped thin films of YBCO are investigated by magnetooptical imaging. By using a numerical inversion scheme of Biot-Savart's law the critical current…