|
|||||
|
|
Improvement in superconductivity of TlBa2CaCu2Oy system by introduction of oxygen loss |
|
| Authors: | S Nakajima M Kikuchi Y Syono K Nagase T Oku N Kobayashi D Shindo and K Hiraga |
| Institution: | a Hachioji Research Center, CASIO Computer Co. Ltd, 2951-5 Ishikawa-cho, Hachioji 192, Japan b Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980, Japan c College of Education, Tohoku University, Kawauchi, Aoba-ku, Sendai 980, Japan |
| Abstract: | The Tc and oxygen content of TlBa2CaCu2Oy have been investigated by quenching experiments, in which the heat-treated samples were dropped into liquid nitrogen. The oxygen loss, v, of TlBa2CaCu2Oyo ? v was determined by thermogravimetry in a nitrogen atmosphere using an oxygen-annealed specimen of TlBa2CaCu2Oyo and also by measurements of the weight differences before and after quenching. Tc increased from 80 K of the oxygen-annealed specimen up to about 110 K with increasing oxygen loss up to v = 0.035 by annealing at 500°C in a nitrogen atmosphere. Judging from the high Tc above 110 K achieved by a small oxygen loss about v = 0.035, the as-sintered oxygen-annealed TlBa2CaCu2Oyo specimen was in the over-doping state and probably has an oxygen vacancy of 7 ? yo0. |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ | |