Magnetic-field and temperature dependence of the critical current in thin epitaxial films of the high-temperature superconductor YBa2Cu3O7−δ

2002 ◽  
Vol 28 (3) ◽  
pp. 172-183 ◽  
Author(s):  
Yu. V. Fedotov ◽  
S. M. Ryabchenko ◽  
É. A. Pashitskiı̆ ◽  
A. V. Semenov ◽  
V. I. Vakaryuk ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Temperature Dependence ◽  
Critical Current ◽  
High Temperature Superconductor ◽  
Epitaxial Films

scholarly journals Механизм формирования критического тока высокотемпературных сверхпроводников, содержащих сквозные микроскопические дефекты

2021 ◽  
Vol 63 (1) ◽  
pp. 65
Author(s):  
А.Н. Максимова ◽  
В.А. Кашурников ◽  
А.Н. Мороз ◽  
И.А. Руднев
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Magnetic Flux ◽  
Critical Current ◽  
High Temperature Superconductor ◽  
Physical Mechanism ◽  
Characteristic Size ◽  
Pinning Centers ◽  
The Magnetic Field ◽  
Qualitative Picture

The critical current of a model high-temperature superconductor (HTSC) with defects in the form of through holes (antidots) with a characteristic size greater than or of the order of the penetration depth of the magnetic field is calculated. To do this, the subprocesses equivalent to the trapping of the magnetic flux by the hole and the creation of a vortex at the edge of the hole are introduced into the model of layered HTSC. It is shown that accounting for these subprocesses leads to the appearance of a physical mechanism that allows us to correctly describe the non-monotonic dependence of the critical current on the characteristic size of the antidot, similar to that observed in the experiment. Calculations were performed for a pure superconductor and a superconductor containing nanoscale pinning centers. It is shown that the presence of nanoscale pinning centers along with antipoints does not change the qualitative picture of the influence of the antidot radius on the pinning character of the magnetic flux and the behavior of the critical current in the HTSC.

The activation energy U(T,B) in high temperature superconductor

2020 ◽  
Vol 92 (2) ◽  
pp. 20601
Author(s):  
Abdelaziz Labrag ◽  
Mustapha Bghour ◽  
Ahmed Abou El Hassan ◽  
Habiba El Hamidi ◽  
Ahmed Taoufik ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Activation Energy ◽  
Phase Diagram ◽  
High Temperature ◽  
Apparent Activation Energy ◽  
High Temperature Superconductor ◽  
Flux Flow ◽  
Resistivity Measurements ◽  
Vortex Phase ◽  
The Magnetic Field

It is reported in this paper on the thermally assisted flux flow in epitaxial YBa2Cu3O7-δ deposited by Laser ablation method on the SrTiO3 substrate. The resistivity measurements ρ (T, B) of the sample under various values of the magnetic field up to 14T in directions B∥ab-plane and B∥c-axis with a dc weak transport current density were investigated in order to determine the activation energy and then understand the vortex dynamic phenomena and therefore deduce the vortex phase diagram of this material. The apparent activation energy U0 (B) calculated using an Arrhenius relation. The measured results of the resistivity were then adjusted to the modified thermally assisted flux flow model in order to account for the temperature-field dependence of the activation energy U (T, B). The obtained values from the thermally assisted activation energy, exhibit a behavior similar to the one showed with the Arrhenius model, albeit larger than the apparent activation energy with ∼1.5 order on magnitude for both cases of the magnetic field directions. The vortex glass model was also used to obtain the vortex-glass transition temperature from the linear fitting of [d ln ρ/dT ] −1 plots. In the course of this work thanks to the resistivity measurements the upper critical magnetic field Hc2 (T), the irreversibility line Hirr (T) and the crossover field HCrossOver (T) were located. These three parameters allowed us to establish a phase diagram of the studied material where limits of each vortex phase are sketched in order to optimize its applicability as a practical high temperature superconductor used for diverse purposes.

scholarly journals Measurements and Analysis of AC Losses in HTS Windings of Electrical Machine for Different Operation Modes

2021 ◽  
Vol 11 (6) ◽  
pp. 2741
Author(s):  
Sergey Zanegin ◽  
Nikolay Ivanov ◽  
Vasily Zubko ◽  
Konstantin Kovalev ◽  
Ivan Shishov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
High Temperature Superconductor ◽  
High Temperature Superconductors ◽  
Transport Current ◽  
Operating Conditions ◽  
Ac Losses ◽  
Electrical Machine ◽  
2Nd Generation ◽  
Motor Mode

The article is devoted to the study of losses in devices based on high-temperature superconductors of the 2nd generation. The complexity of the devices under study increases from a single rack coil to a winding assembled from several coils, and finally to an electric machine operating in generator mode. This is the way to experimentally study the behavior of 2nd generation high temperature superconductor (2G HTS) carrying a transport current in various conditions: self-field, external DC, and AC magnetic field. Attention is also paid to the losses in the winding during its operation from the inverter, which simulates the operating conditions in the motor mode of a propulsion system.

Magnetic Coupling in La0.7Ca0.3MnO3/YBa2Cu3O7/La0.7Ca0.3MnO3 Trilayers

2009 ◽  
Vol 289-292 ◽  
pp. 303-309
Author(s):  
N.M. Nemes ◽  
C. Visani ◽  
J. Garcia-Barriocanal ◽  
F.Y. Bruno ◽  
Z. Sefrioui ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Carrier Density ◽  
High Temperature Superconductor ◽  
Hysteresis Loops ◽  
Magnetic Coupling ◽  
Oxygen Depletion ◽  
Free Carrier ◽  
Half Metallic ◽  
Free Carrier Density

We report on the interplay between ferromagnetism and superconductivity in trilayers La0.7Ca0.3MnO3/YBa2Cu3O7/La0.7Ca0.3MnO3 made of half metallic manganite and high temperature superconductor cuprate. Samples with a fully oxygenated cuprate show a magnetic field interval where the magnetizations of the manganite are aligned antiparallel. A considerable magnetoresistance accompanies the switching between magnetization configurations (parallel vs. antiparallel) of the manganite moments. Suppression of the free carrier density of the cuprate which occurs upon oxygen depletion, results in deep modifications in the shape of the normal state hysteresis loops indicating that there may be a magnetic coupling mediated by free carrier density of the cuprate. This result outlines the importance of quasiparticle transmission in the interplay between ferromagnetism and superconductivity in this kind of samples.

Current sharing between the metallic and superconducting layers of high temperature superconductor coated conductors operated above their critical current

2011 ◽  
Vol 109 (3) ◽  
pp. 033915 ◽  
Author(s):  
Pierre Bernstein ◽  
Conor McLoughlin ◽  
Yohann Thimont ◽  
Frédéric Sirois ◽  
Jonathan Coulombe
Keyword(s):  
High Temperature ◽  
Critical Current ◽  
High Temperature Superconductor ◽  
Coated Conductors ◽  
Current Sharing

HIGH MAGNETIC FIELD HALL EFFECT AND MAGNETORESISTANCE STUDIES OF Y-Ba-Cu-O: A HIGH Tc SUPERCONDUCTOR

1987 ◽  
Vol 01 (02) ◽  
pp. 413-417
Author(s):  
J.D. Hettinger ◽  
A.G. Swanson ◽  
J.S. Brooks ◽  
Y.P. Ma
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Transition Temperature ◽  
Hall Effect ◽  
High Temperature Superconductor ◽  
Strong Dependence ◽  
Zero Magnetic Field ◽  
High Tc ◽  
Relative Percentage ◽  
High Tc Superconductor

We have measured the transition temperature, critical field, magnetoresistance, and Hall effect for the high temperature superconductor Y-Ba-Cu-O in magnetic fields up to 23T in the temperature range 4.2 to 125K. Meissner studies at zero magnetic field were also performed in some cases. We find a strong dependence of these parameters on the relative percentage of the correct phase of Y-Ba-Cu-O in the sample. We report new results on magnetoresistance and Hall effect in these materials.

The Study of Switching Dynamics in Planar Structures Based on Epitaxial Films of YBa2Cu3O7-δ High-Temperature Superconductor

2020 ◽  
Vol 33 (12) ◽  
pp. 3695-3704
Author(s):  
N. A. Tulina ◽  
I. Yu. Borisenko ◽  
I. M. Shmytko ◽  
А. А. Ivanov ◽  
A. N. Rossolenko ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperature Superconductor ◽  
Epitaxial Films ◽  
Planar Structures ◽  
Switching Dynamics
Sign in / Sign up

Export Citation Format

Share Document