Related papers: Strong Pinning in High Temperature Superconductors
Transport measurements carried out on twinned ybco films are compared to the predictions of a previously proposed model suggesting that the vortices move along the films twin boundaries that behave as rows of Josephson weak links…
Measurements of the Hall effect and the resistivity in twinned YBa2Cu3O7-delta thin films in magnetic fields B oriented parallel to the crystallographic c-axis and to the twin boundaries reveal a double sign reversal of the Hall coefficient…
We investigate the in-field critical current density Jc(B) of SNS Josephson Junctions (JJs) and polycrystalline superconductors with grain boundaries modelled as Josephson type planar defects, both analytically and through computational…
We report the influence of intrinsic superconducting parameters on the vortex dynamics and the critical current densities of a MgB$_2$ thin film. The small magnetic penetration depth of \lambda = 50 nm at T=4 K is related to a clean…
The effect of $\alpha$-particle irradiation on a NdFeAs(O,F) thin film has been investigated to determine how the introduction of defects affects basic superconducting properties, including the critical temperature $T_c$ and the upper…
Magnetic fields penetrate a type-II superconductor as magnetic flux quanta, called vortices. In a clean superconductor they arrange in a hexagonal lattice, while by adding periodic artificial pinning centers many other arrangements can be…
We have grown and characterized 30 nm thick YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO) films, deposited by pulsed laser deposition on both MgO (110) and SrTiO$_3$ (001) substrates, which induce opposite strain to the superconducting layer. By…
The confinement of a superconductor in a thin film changes its Fermi-level density of states and is expected to change its critical temperature $T_c$. Previous calculations have reported large discontinuities of $T_c$ when the chemical…
We studied flux pinning in exfoliated FeTe$_{0.6}$Se$_{0.4}$ thin-film devices with a thickness $d$ from 30 to 150 nm by measuring the critical current density $J_{\mathrm{c}}$. In bulk FeTe$_{0.6}$Se$_{0.4}$, the flux pinning has been…
A series of polycrystalline SmFeAs1-xOx bulks was prepared to systematically investigate the influence of sample density on flux pinning properties. Different sample densities were achieved by controlling the pelletizing pressure. The…
Critical current density (Jc) is one of the major limiting factors for high field applications of iron-based superconductors. Here, we report that Mn-ions are successfully incorporated into nontoxic superconducting (Li,Fe)OHFeSe films.…
We have investigated the zero-field critical supercurrent of YBa$_2$Cu$_3$O$_{7-\delta}$ bridges patterned from 50 nm thick films as a function of bridge width, ranging from 2 $\mu$m to 50 nm. The critical current density monotonically…
The superconducting and critical current properties of thin films of NiBi3 formed on the surface of carbon microfibers and sapphire substrates are reported. The NiBi3 coated carbon microfibers were prepared by reacting 7 {\mu}m diameter…
We have investigated the resistive response of high Tc thin films submitted to a high density of current. For this purpose, current pulses were applied into bridges made of Nd(1.15)Ba(1.85)Cu3O7 and Bi2Sr2CaCu2O8. By recording the time…
The field-angular dependence and anisotropy of the critical current density in iron-based superconductors is evaluated using a phenomenological approach featuring distinct anisotropy factors for the penetration depth and the coherence…
Adding Au nanoparticles to YBa$_2$Cu$_3$O$_{7-\delta}$ thin films leads to an increase of the superconducting transition temperature $T_{\rm c}$ and the critical current density $j_{\rm c}$. While the higher $j_{\rm c}$ can be understood in…
We report the comprehensive comparative analysis of the upper critical magnetic fields $\mu_{0}H_{c2}(0)$ obtained within Ginzburg-Landau and Werthamer-Helfand-Hohenberg theories for optimally-doped $YBa_2Cu_3O_{7-\delta}$ thin films. For…
The tilt modulus of a defective Abrikosov vortex lattice pinned by material line defects is computed using the boson analogy. It tends to infinity at long wavelength, which yields a Bose glass state that is robust to the addition of weak…
The normal-state conductivity and superconducting critical temperature of oxygen-deficient YBa2Cu3O7-x can be persistently enhanced by illumination. Strongly debated for years, the origin of those effects -- termed persistent…
We report on electrical transport properties of epitaxial Ba(Fe1-xNix)2As2 thin films grown by pulsed laser deposition in static magnetic fields up to 35 T. The thin film shows a critical temperature of 17.2 K and a critical current density…