ELECTRONIC STRUCTURE OF Hg0.8Pb0.2Ba2Ca2Cu3O8+δ: THE ROLE OF Pb DOPING, OXYGEN DOPING AND HIGH PRESSURE

The effects of Pb doping, oxygen doping (δ= 0.1,0.2,0.4 and 0.5) and high pressate (4, 8, 15 and 20GPa) on the electronic structure of Hg_0.8Pb_0.2Ba₂Ca₂Cu₃O_8+δ have been examined by the recursion method. Our calculations show that Pb doping only decreases the hole concentration slightly and oxygen doping increases the hole concentration monotonically and significantly as δ varies from 0 to 0.5, with each excess oxygen atom contributing about 1.7 holes to the CuO₂ layers. The optimal δ is estimated to be around 0.4, The hole conceatration increases initially with pres-sure but decreases as P > 8GPa (i.e., dn/dP does change sign at ～ 8GPa). The suppressed T_c(P) by Pb substitution has to be described in the modified Neumeier's model.     

ELECTRONIC STRUCTURE OF Hg0.8Pb0.2Ba2Ca2Cu3O8+δ: THE ROLE OF Pb DOPING,OXYGEN DOPING AND HIGH PRESSURE

The effects of Pb doping, oxygen doping ($\delta$= 0.1,0.2,0.4 and 0.5) and high pressate (4, 8, 15 and 20GPa) on the electronic structure of Hg_0.8Pb_0.2Ba₂Ca₂Cu₃O_8+δ have been examined by the recursion method. Our calculations show that Pb doping only decreases the hole concentration slightly and oxygen doping increases the hole concentration monotonically and significantly as δ varies from 0 to 0.5, with each excess oxygen atom contributing about 1.7 holes to the CuO₂ layers. The optimal δ is estimated to be around 0.4, The hole conceatration increases initially with pres-sure but decreases as P > 8GPa (i.e., dn/dP does change sign at ～ 8GPa). The suppressed T_c(P) by Pb substitution has to be described in the modified Neumeier's model.     

关于掺杂C60超导体超导电性的一种可能机制

本对掺杂Ｃ６０超导体建议了一种可能的超导机制，即巡游载流子与局域电子对相互作用，此机制对Ｒｂ３Ｃ６０的超导转变、磁场穿透深度、相干长度、热力学临界磁场以及Ｔｃ处的经热跳跃作了计算，结果和实验基本一致，掺杂Ｃ６０超导体与高温氧化物超导化玎比更多地表现出传统ＢＣＳ超导体行为，对此进行了讨论。