摘要
本文叙述了在模拟实用的低温外壳中以高T_C YBCO薄膜进行了超导Josephson结在核辐射探测器领域内的应用研究:1.高T_C YBCO桥结最佳几何尺寸的选取。在厚为2000—3000的高T_C YBCO薄膜上制备了2×2,2×6,3×30,5×40,10×50,20×60μm^2的结,实验结果表明5×40,10×50μm^2的两种结对射线的灵敏度最高,信号电压未经任何放大可达40μV,而且随源强增加而增加。2.利用升压变压器耦合经前放和主放放大成形后已观测到59.5keV低能γ射线的单次脉冲计数。3.经过连续五次温度循环性能较好。4.高T_C YBCO超导材料的抗辐照性与高T_C超导材料性能的好坏有关。这些结果表明利用高T_C超导薄膜的Josephson结有可能研制出用以测量核辐射能谱的高T_C超导核辐射探测器。
For practical use, we have fabricated bridge junction of high Tc YBCO film and made many experiments on. them in cryogenic capsules, This paper of the high T superconducting detector describes several important factors.1.Choosing proper geometrical sizes of high Tc YBCO bridge junction. We fabricated bridge junction of various geometrical sizes,and their widths to lengths are respectively 2×2, 2×6, 3×30, 5×40, 10×50 and 20×60μm2, The results of experiments show that two kinds of bridge junctions of 50×40 and 10×50μm2 are more sensitive to nuclear radiation than the other kinds. The voltages of signals are as high as 40μV without amplifier, and increase with radiactivety.2.Using stepping-up transformer, preamplifier and spectrum amplifier, we observed counts to low energy γ-ray of 241Am 59.5keV.3.After being cooled to 78K and heated to room temperature five times, the performance of bridge junction was as good as before being cooled and heated.4.The radio-resistance of bridge junction is related to the quality of high Tc superconductive materials.These experimental results show that it's possible to use high Tc superconducting Josephson junction to measure the energy spectrum of nuclear radiation.
出处
《低温与超导》
CAS
CSCD
北大核心
1992年第3期43-47,共5页
Cryogenics and Superconductivity
