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تسجيل مستخدم جديدAngular dependence of resistivity in the superconducting state of NdFeAsO$_{0.82}$F$_{0.18}$ single crystals
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We report the results of angle dependent resistivity of NdFeAsO$_{0.82}$F$_{0.18}$ single crystals in the superconducting state. By doing the scaling of resistivity within the frame of the anisotropic Ginzburg-Landau theory, it is found that the angle dependent resistivity measured under different magnetic fields at a certain temperature can be collapsed onto one curve. As a scaling parameter, the anisotropy $Gamma$ can be determined for different temperatures. It is found that $Gamma(T)$ increases slowly with decreasing temperature, varying from $Gamma simeq$ 5.48 at T=50 K to $Gamma simeq$ 6.24 at T=44 K. This temperature dependence can be understood within the picture of multi-band superconductivity.
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This paper is no longer active and will NOT appear in print. For new data and analysis, please see: arXiv:0903.2220
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