Related papers: Normal state properties of high angle grain bounda…
We report the structural, superconducting, magnetic and granular properties of Y1-xCaxBa2Cu3O7; x = 0.0, 0.1, 0.2 and 0.3. Rietveld fitted X-ray diffraction data confirms the single phase formation for all the samples. The orthorhombicity…
The critical current density flowing across low angle grain boundaries in YBa$_2$Cu$_3$O$_{7-\delta}$ thin films has been studied magnetometrically. Films (200 nm thickness) were deposited on SrTiO$_3$ bicrystal substrates containing a…
Grain boundaries affect properties of polycrystalline materials. The influence of a boundary is largely determined by its energy. Grain boundary energy is often portrayed as a function of macroscopic boundary parameters representing grain…
In this paper we present the resistivity, the Seebeck effect, and the thermal conductivity measurements on a MgB2 sintered sample. Such transport properties highlight the role of the junctions between the grains to a different extent. In…
We have investigated the transport and noise properties of submicron YBCO bicrystal grain-boundary junctions prepared using electron beam lithography. The junctions show an increased conductance for low voltages reminiscent of Josephson…
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…
We explore the statistical properties of grain boundaries in the vortex polycrystalline phase of type II superconductors. Treating grain boundaries as arrays of dislocations interacting through linear elasticity, we show that…
We have performed a detailed study of the tunneling spectra of bicrystal grain boundary junctions (GBJs) fabricated from the HTS YBCO, BSCCO, LSCO, and NCCO. In all experiments the tunneling direction was along the CuO planes. With the…
We investigate transport in a granular metallic system at large tunneling conductance between the grains, $g_T\gg 1$. We show that at low temperatures, $T\leq g_T\delta $, where $\delta$ is the single mean energy level spacing in a grain,…
Unconventional superconductivity remains one of the central unsolved problems in quantum materials, and revealing its connection to the normal state is widely believed to be key to uncovering the pairing mechanism. Previous efforts have…
This study investigates the influence of various growth parameters on normal-state resistivity and superconducting transition temperature Tc of granular aluminum films. Specifically, we focus on the effects of oxygen flow and aluminum…
The purpose of this article is to discuss a view concerning key datasets of the properties of grain boundaries in high-Tc superconductors that was recently expressed in Ref. 1. The reference also criticizes our research. Using examples I…
We investigate transport in a granular metallic system at large tunneling conductance between the grains. We show that at low temperatures, $T\leq g_T\delta $, where $\delta$ is the single mean energy level spacing in a grain, the coherent…
The thermal conductivity study on the pyrochlore structured ceramics is important for utilization of these materials as an inert matrix fuel, electrolytes for oxide fuel cell and thermal barrier coating. The impact of porosity, structural…
A discrete model and the regular solution approximation are applied to describe the effect of grain boundary motion on grain boundary phase transformations in a binary alloy. The model predicts all thermodynamic properties of the grain…
Orientation effects on the resistivity of copper grain boundaries are studied systematically with two different atomistic tight binding methods. A methodology is developed to model the resistivity of grain boundaries using the Embedded Atom…
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…
I present a new phenomenological model for the normal state transport properties of high-Tc cuprates. In particular, I identify a form of scattering rate that may account, qualitatively and quantitatively, for the normal state…
We performed detailed ac susceptibility measurements on Pr$_{1-x}$Ag$_x$MnO$_3$ ($x$=0.15, 0.20) manganites and observed unusual and interesting features, which are associated with the domain walls and the effects of grain-boundaries on…
The ability of single grain boundaries in YBa2Cu3Ox bicrystalline rings to carry electrical current is found to be significantly enhanced under hydrostatic pressure. Nearly hydrostatic pressures are applied to the alkali metals Li, Na, and…