Gd掺杂对Bi_2Sr_2Ca_(1-x)Gd_xCu_2O_y单晶载流子浓度和各向异性电阻率的影响  

Gd DOPING EFFECT ON THE CARRIER CONCENTRATION AND ANISOTROPIC RESISTIVITIES OF Bi_2Sr_2Ca_(1-x)Gd_xCu_2O_y SINGLE CRYSTALS

作　　者：赵霞[1] 孙学峰[1] 范晓娟[1] 吴文彬[2] 朱长飞[1] 李晓光[1] 

机构地区：[1]中国科学技术大学材料科学与工程系 [2]中国科学技术大学结构分析开放研究实验室,合肥230026

出　　处：《低温物理学报》1999年第6期468-471,共4页Low Temperature Physical Letters

基　　金：国家超导中心资助;国家自然科学基金

摘　　要：系统地研究了Ｇｄ 掺杂对Ｂｉ２Ｓｒ２Ｃａ１ － ｘＧｄｘＣｕ２Ｏｙ 单晶超导电性及各向异性电阻率的影响．Ｔｃ 满足Ｔｃ／ Ｔｃ，ｍａｘ ＝ １ － ８２ ．６（ ａｘ＋ ｂ）２ ，并随Ｇｄ 含量的增加而下降，这是由于Ｇｄ 掺杂引起载流子浓度减小所导致．在ｘ≥０ ．１９ 时，ρａｂ（ Ｔ） 在Ｔｃ 附近有类半导体行为，ｄρａｂ／ｄＴ随Ｇｄ 含量增大而增大．ρｃ（ Ｔ） 呈半导体行为，并可用唯象公式ρｃ（ Ｔ） ＝ （ ａ／ Ｔ）ｅｘｐ（Δ／ Ｔ） ＋ ｂＴ＋ ｃ 加以描述．电阻率各向异性ρｃ／ρａｂ 随掺杂浓度增大而增大．Gd doping effect on the superconductivity and anisotropic resistivity of Bi\-2Sr\-2Ca\-\{1- x \}Gd\- x Cu\-2O\- y single crystals were carefully studied. It was found that T\-c can be described as T\-c / T\-\{c ,max\}=1-82.6( ax+b )\+2 and the decrease of it was due to the hole filling effect. In plain resistivity ρ\-\{ab\}(T) showed semiconductor like behavior near T\-c when x ≥0.19. The slope d ρ\-\{ab\}(T) /d T increased with the increase of Gd content. ρ\-c(T) showed semiconductor behavior and can be reproduced by the phenomenological formula \$ρ\-c(T)=(a/T) exp(Δ /T)+bT+c\$. The ratio ρ\-c/ρ\-\{ab\} increased with the doping of Gd.

关 键 词：GD掺杂 载流子浓度 超导电性 各向异性电阻率 

分 类 号：O514[理学—低温物理] O511.2[理学—物理]