Related papers: What limits supercurrents in high temperature supe…
High critical temperature superconductors have zero power consumption and could be used to produce ideal electric power lines. The principal obstacle in fabricating superconducting wires and tapes is grain boundaries-the misalignment of…
The results of dc, microwave and magnetic measurements of YBCO bicrystal junctions on r-cut sapphire are presented. The junctions with high resistance 10-20 W and IcRN= 1-2 mV and tolerance of RNS around 30% on chip allow to create…
Identifying the origins of suppression of the critical current at grain boundaries of high-critical-temperature superconductors, such as cuprates and iron-based superconductors, is a crucial issue to be solved for future applications with…
For many applications of polycrystalline high-Tc superconductors the small critical currents of the grain boundaries pose a severe problem. To solve this problem we derive novel designs for the microstructure of coated conductors.
We propose and implement a direct experimental test for subdominant superconducting phases with broken time-reversal symmetry in d-wave superconductors. The critical current of 45-degree asymmetric grain boundary junctions are shown to be…
It has been hypothesized that the variation of the critical currents in Nb/Al-AlO$_x$/Nb junctions is due to, among other effects, the presence of grain boundaries in the system. Motivated by this, we examine the effect of grain boundaries…
Flux pinning scaling laws were developed to explain the observed increase in the critical current density Jc caused by increased density of grain boundaries in polycrystalline low temperature superconductors (LTS) such as Nb3Sn. For four…
Transport critical current measurements have been performed on 5 degree [001]-tilt thin film YBa2Cu3O7-delta single grain boundaries with magnetic field rotated in the plane of the film, phi. The variation of the critical current has been…
Grain boundaries are critical for determining the functionality of polycrystalline materials. Here we present on the structural $\&$ transport properties of grain boundaries in the unconventional superconductor CeCoIn$_5$. We provide a…
The twist angle {\gamma} dependence of the Josephson critical current of d-wave superconductors in one junction and a granular system is considered. Our results show that the twist angle {\gamma} dependence of the d-wave Josephson critical…
We calculate the dc supercurrent through a Josephson tunnel junction consisting of an antiferromagnetic (AF) interlayer sandwiched between two d-wave superconductors (d). Such d/AF/d junctions exhibit a rich dependence of the Josephson…
In this work we investigate the effect of each different heat treatment stage in the fabrication of Bi2Sr2CaCu2O8+d superconducting wires on intra-grain and inter-grain superconducting properties. We measure magnetic critical temperature Tc…
Grain boundary bicrystal Josephson junctions of the electron-doped infinite-layer superconductor Sr$_{1-x}$La$_x$CuO$_2$ ($x = 0.15$) were grown by pulsed laser deposition. BaTiO$_3$-buffered $24\,^\circ$ [001]-tilt symmetric SrTiO$_3$…
Strong correlations are known to severely reduce the mobility of charge carriers near half-filling and thus have an important influence on the current carrying properties of grain boundaries in the high-$T_c$ cuprates. In this work we…
We calculate the critical current $I_c$ across in-plane (001) tilt grain boundary junctions of high temperature superconductors. We solve for the electronic states corresponding to the electron-doped cuprates, two slightly different…
The importance of the distribution and ``weakness'' of grain boundary junctions in the magnetic field dependence of the transport critical current in HTc films is assessed through simulations. The system is studied with the applied field…
The magneto-conductance in YBCO grain boundary Josephson junctions, displays fluctuations at low temperatures of mesoscopic origin. The morphology of the junction suggests that transport occurs in narrow channels across the grain boundary…
A study has been perfomed on the superconducting critical current density J_{c} flowing across low angle grain boundaries in epitaxial thin films of YBa{2}Cu{3}O{7-d} (YBCO). The materials studied were dual grain boundary rings deposited on…
Iron-based superconductors have great potential for high-power applications due to their prominent high-field properties. One of the central issues in enhancing the critical current density of iron-based superconducting wires is to reveal…
The Fe-based superconductors (FBS) are an important new class of superconducting materials. As with any new superconductor with a high transition temperature and upper critical field, there is a need to establish what their applications…