【摘要】 测量了高质量的GdBa₂Cu₃O_7-x薄膜的电阻及磁阻曲线,应用Lawrence-Doniach理论对实验曲线进行了拟合,得到了一组自洽且合理的参数值,由ln(σ—σ_?)-Int曲线可以明显地看到存在一个二维向三维的转变。更多还原

【Abstract】 The fluctuation conductivity and magnetoresistance of a high quality GdBa2Cu3- O7-x c-axis-oriented epitaxial film have been investigated. The measured excess con-ductivity in the temperature range 96-280K is fitted by the Lawrence Doniach the-ory. By using this theory, reasonable values of parametes α,b,?ξc,Tc,d are obtained and a 2D-to-3D transition is observed according to the ln(σ-σx)-lnt curve.更多还原