Title :
Temperature dependence of the anisotropy in magnetic relaxation in YBa2Cu3O7-2 thin films
Author :
Vitta, Satish ; Stan, M.A. ; Alterovitz, S.A.
Author_Institution :
NASA Lewis Res. Center, Cleveland, OH, USA
fDate :
3/1/1991 12:00:00 AM
Abstract :
The relaxation of diamagnetic magnetization in the c axis aligned YBa2Cu3O7-x thin films is studied as a function of orientation and temperature in the range of 5-50 K at H=0.2 T. The magnetization M(T,H) in the orientations H||c and H⊥c and at all the temperatures is found to decrease logarithmically with time t. The activation energy for the movement of flux lines U is found to be 30-110 meV in the range 5-50 K. For H||c, U increases continuously with T, whereas for H⊥c, U has two apparent maxima: at T=10 K and T>50 K. These results are discussed in terms of the thermally activated flux motion model
Keywords :
barium compounds; diamagnetic properties of substances; flux flow; high-temperature superconductors; magnetic relaxation; magnetisation; superconducting thin films; yttrium compounds; 5 to 50 K; activation energy; c axis aligned YBa2Cu3O7-x thin films; diamagnetic magnetization; flux lines; high temperature superconductivity; magnetic relaxation anisotropy; orientation dependence; temperature dependence; thermally activated flux motion model; Anisotropic magnetoresistance; Magnetic anisotropy; Magnetic flux; Magnetization; Perpendicular magnetic anisotropy; Superconducting magnets; Superconducting transition temperature; Temperature dependence; Temperature distribution; Transistors;
Journal_Title :
Magnetics, IEEE Transactions on
