摘要
使用外延YBa_2Cu_3O_7薄膜,测量了低温下(液氮或液氦温度)质子辐照对样品输运性质的影响。不仅观察到由低温辐照引起的样品超导转变温度Tc下降及电阻率P上升,还观察到dp/dT的上升和发生金属至非金属的相变。经室温热循环的样品显示出强烈室温退火效应。近60％由辐照引起的样品电阻升高和Tc下降可以得到恢复,并可伴随发生非金属至金属的相变,在La-Sr-Cu-O薄膜的低温辐照实验中观察到了类似的室温退火效应,对实验结果的分析表明,YBa_2Cu_3O_7高Tc氧化物超导体的电子能带结构对由低温辐照引入的无序分布缺陷十分敏感。
The influence of low temperature proton irradiation on the transport property of high Tc oxide Y-Ba-Cu-O and La-Sr-Cu-O is studied by a standard four probe method. After irradiation, besides the resistivity of the sample increases and the superconducting transition temperature Tc decreases, the dp/dT of the sample increases and a metal-nonmetal phase trasition occurs. A strong annealing effect is found during warming up irradiated samples to room temperature. After room temperature annealing, nearly 60% of changes of the sample resistance and Tc which were caused by low temperature proton irradiation can be recovered. These phenomena can be attributed to that the electronic band structure of the high Tc oxide superconductor is very sensitive to the random defects.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第5期768-775,共8页
Acta Physica Sinica
