Pulse magnetization and voltage-current characteristic of YBa2Cu3O7-x film

11th European Conference on Applied Superconductivity

Dorofeev, G.^1 ; Drobin, V.^2 ; Malinowski, H.^2

Kurchatov Institute, Moscow, Russia^1

JINR, Dubna, Russia^2

关键词: Electrical field;    External magnetic field;    Field dependence;    Flux-flow resistance;    Heaviside functions;    Linear dependence;    Low temperature superconductors;    Voltage-current characteristics;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/1/012009/pdf
DOI  :  10.1088/1742-6596/507/1/012009

来源: IOP

【 摘 要 】

The measurements of YBa2Cu3O7-Xfilms magnetization are made at ramp rate of the external magnetic field up to 105T/sec at temperature of liquid nitrogen in fields up to 4 T. The linear dependence of the magnetic moment of films on rate of an external magnetic confirms, that in the large electrical fields down to 1 V/cm the voltage-current characteristic can be described by the flux flow resistance Rflow and the critical current Jflow, similar to traditional low temperature superconductors: E = Rflow·(J - Jflow)·Θ(J - Jflow), where θ is the Heaviside function. The experimental data of pulse magnetization of films of thickness 0,2 microns on substrates Al2O3of size 10 × 10 mm with critical currents higher 106A/cm2have allowed to determine field dependence of the critical current and the flux flow resistance. In particular the resistance Rflow is increased approximately by 3 times for increase of an external field from 0,5 up to 4 T, and the Jflow values approach the critical currents determined from quasi-stationary magnetization.