Seminarium Międzynarodowego Laboratorium Silnych Pól Magnetycznych i Niskich Temperatur PAN
ul. Gajowicka 95, sala seminaryjna (nowy budynek, II piętro)
Magnetization and critical current of calcium-doped YBa2Cu3O7-x composite films
I.A. Rudnev, A.P. Menushenkov, A.V. Blednov, V.N. Chepikov, S.V. Samoylenkov
National Research Nuclear University MEPHI (Mos-cow Engineering Physics Institute), Moscow, Russia
In the report we present results of the study of magnetization of Y1-хCaxBa2Cu3O7-d HTS films deposited on the metallic substrate. Magnetisation measurements were carried out in a wide temperature range 4 – 77 K and magnetic fields up to 14 T. Based on critical state model the analysis of the influence the effect of calcium concentration on the critical current in the samples was performed. It was found that the change in Ca concentration causes the decrease in value of critical current density jc. The increase of temperature leads to an enhancement of the observed effect. At T = 4.2 K and in the magnetic fields higher than 8 T the jc reduction was found to be insignificant. This fact may indicate the possibility of jc growth in strong magnetic fields due to increase in carrier concentration caused by replacing Y3+ by Ca2 +.