Bi-2223/Ag异质结的光生电压效应研究  

Photo-generated Voltage Effect of Bi-2223/Ag Heterojunction

作　　者：马志攀 楚庄 杨枫 刘志勇 苏健[1,2] 宋桂林 常方高[1,2] MA Zhi-pan;CHU Zhuang;YANG Feng;LIU Zhi-yong;SU Jian;SONG Gui-lin;CHANG Fang-gao(College of Physics&Materials Science,Henan Normal University,Xinxiang 453007,China;Henan Key Laboratory of Photovoltaic Materials,Xinxiang 453007,China)

机构地区：[1]河南师范大学物理与材料科学学院,新乡453007 [2]河南省光伏材料重点实验室,新乡453007

出　　处：《人工晶体学报》2018年第3期582-587,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(60571063);河南省基础与前沿技术研究(162300410086)

摘　　要：在50~340 K不同温度下,利用紫色激光(λ=405 nm)对银/铋锶钙铜氧2223异质结界面进行辐照,观测到明显的光生电压效应,发现光生电压的极性分别在超导转变温度TC与320 K附近发生了反转,排除了激光产生的热电势是产生光生电压的原因,分析表明银/铋锶钙铜氧2223异质结界面处存在内建电场:光生电压由异质结界面处的内建电场分离光生电子-空穴对产生的。超导转变温度TC之下以及320 K以上,内建电场方向从超导体指向金属电极;超导转变温度TC与反向温度320 K之间,内建电场从金属指向超导体。Photogenerated voltage of Ag/Bi2223 was observed by purple-laser(A=405 nm)irradiation range from 50 K to 340 K,it was found that the photogenerated voltage changed in the direction around the superconducting transition temperature Tc and 320 K respectively.By analyzing the relationship between the photogenerated voltage effect with the superconducting properties and the heterojunction interface of Ag/Bi2223,it was excluded that the thermoelectric effect induced by laser irradiation is the cause of the photogenerated voltage.We showed that there a built-in electrical field exists the superconductor-normal metal interface,which provided the separation force for the photo-induced electron-hole pairs.The direction of built-in electrical field which below Tc and above 320 K points from the superconductor to the metallic electrode.Between Tc and 320 K,the interface field points from metal to superconductor.

关 键 词：光生电压效应 界面 铜氧化物超导 内建电场 

分 类 号：TB333[一般工业技术—材料科学与工程] O469[理学—凝聚态物理]