摘要
采用低温太赫兹时域光谱系统,测试了高温超导Tl_2Ba_2CaCu_2O_(8+x)薄膜的太赫兹透射谱,并提取了它在不同温度下的太赫兹电导率.研究过程中发现提取后的参数存在电导率随频率波动大、与理论值偏差较大等问题.通过对基片厚度和太赫兹波入射角度的误差对高温超导薄膜电导率的影响进行了分析,结果表明导致数据波动大是由于基片厚度的偏差引起的.针对厚度差的影响,一种矫正方法被提出,通过对厚度的修正,提高了数据提取的质量.
The transmission spectra of the high-temperature superconducting Tl_2Ba_2CaCu_2O_(8+x)(TBCCO)films were measured using terahertz(THz)time domain spectroscopy(TDS),and the THz conductivities at different temperatures were extracted.It is found that the extracted complex conductivity has some problems,such as the large fluctuation of the conductivity with frequency and large deviation from theoretical values.Based on the analysis on how the errors of the substrate thickness and the incident angle of the THz wave affect the extracted complex conductivity of the TBCCO films,it is shown that the large fluctuation of the conductivity is caused by the error of the substrate thickness.Aiming at eliminating influence of the error of the substrate thickness,a correction method is proposed.Through the correction of the substrate thickness,the extracted complex conductivity of the TBCCO films gain great improvement.
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