Reconsideration of Orth Ⅰ and Orth Ⅱ Phases in Ln-System Superconductors  

作　　者：刘跃伟 王路 张酣 

机构地区：[1]Materials Physics Laboratory, State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871

出　　处：《Chinese Physics Letters》2006年第2期453-455,共3页中国物理快报（英文版）

摘　　要：A block model is used to calculate the combinative energy in LnBa2Cu3O7-x （Ln=Y, Er, Nd） systems, and the energy has no difference for orth-Ⅰ and orth-Ⅱ in the plateau range. Namely, no matter what phase it is, when the oxygen deficiency is in the range of δ-0.35-0.55, the plateau appears in the energy -δ curves, and the combinative energy has close correlation with the Tc value. The result in the present work gives some hints to reconsider the role of the order of oxygen defects or its effect on superconductivity in LnBa2Cu3O7-x. The existence of the orth-Ⅱ seems not to be the reason for the plateau in the Tc curve. This is an important problem for LnBa2Cu3O7-x and some suggestion is given in the discussion.A block model is used to calculate the combinative energy in LnBa2Cu3O7-x （Ln=Y, Er, Nd） systems, and the energy has no difference for orth-Ⅰ and orth-Ⅱ in the plateau range. Namely, no matter what phase it is, when the oxygen deficiency is in the range of δ-0.35-0.55, the plateau appears in the energy -δ curves, and the combinative energy has close correlation with the Tc value. The result in the present work gives some hints to reconsider the role of the order of oxygen defects or its effect on superconductivity in LnBa2Cu3O7-x. The existence of the orth-Ⅱ seems not to be the reason for the plateau in the Tc curve. This is an important problem for LnBa2Cu3O7-x and some suggestion is given in the discussion.

分 类 号：O511[理学—低温物理]