Title :
Numerical simulation of current-quenching phenomena for high Tc YBaCuO superconducting thin films
Author :
Nakamiya, T. ; Ikegami, T. ; Ebihara, K.
Author_Institution :
Dept. of Electron. & Inf. Technol., Tokai Univ., Kumamoto, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
The current quenching characteristics of a YBaCuO thin film (1 /spl mu/m thick, 2 mm wide and 8 mm long) on MgO are studied numerically by solving the heat flow equation. The finite element method is applied to solve the equation considering the temperature dependence of the resistance and thermal conductivity, and the effect of the convection coefficient. Currents of different wave forms were fed to the thin films for a few tens of milliseconds in liquid nitrogen to measure the temporal resistance. The substrate temperature at the bottom is kept at 77.3 K. When a ramp current of dI/dt=83.5 A/s (duration: 17 ms) is applied to the current terminals of the YBaCuO thin film, the temperature starts to increase after 10 ms, and reaches a maximum temperature of 155 K (maximum resistance: 7.3 /spl Omega/) at 17 ms for a convection coefficient of 1.0 W/cm/sup 2/ K. The calculated results are compared with experimental data obtained from the resistive characteristics of a YBaCuO superconducting thin film quenched by a current.<>
Keywords :
barium compounds; convection; finite element analysis; high-temperature superconductors; quenching (thermal); superconducting thin films; thermal conductivity; thermal resistance; yttrium compounds; 1 mum; 2 mm; 7.3 ohm; 77.3 to 155 K; 8 mm; MgO; YBaCuO; YBaCuO superconducting thin films; convection coefficient; current quenching characteristics; finite element method; heat flow equation; high Tc superconducting thin films; numerical simulation; resistance; temperature dependence; thermal conductivity; Equations; Finite element methods; Nitrogen; Numerical simulation; Superconducting thin films; Temperature dependence; Thermal conductivity; Thermal resistance; Transistors; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
