多频法测量高温超导薄膜表面电阻

ANALYSIS OF ERROR FOR SURFACE RESISTANCE MEASUREMENTS OF SUPERCONDUCTING FILMS

本文对介质谐振器法测量高温超导薄膜微波表面电阻的方法进行了详细的研究 ,并对测试系统的损耗提出了新的计算方法 .由四个不同直径、相同高度的蓝宝石构成四个谐振器 ,对同一组铜膜进行测量 ,根据金属表面电阻与频率的关系 ,分析测试装置的损耗 ,从而更精确地测出薄膜的表面电阻 .经实验证明 ,此方法能得到比传统测量更为精确的测量结果 .

An intensive research on the dielectric resonator method appropriate to meansure microwave surface resitance of high temperature superconducting (HTS) films was carried out, and a new experimental method i.e.multi frequency method and a system loss formula were presented in this paper. A dielectricc resonator using four different sapphire rods with dimension of the same height but different diameter were employed to measure the surface resistances of Cu films at four different microwave frequencies. The measurement of system loss was then analysed by the system loss formula according to the frequency dependence of the metallic surface resistance. Consequently, the surface resistances of the HTS films could be determined more precisely. Our experimental results verified that the new method was more accurate than the conventional method.