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تسجيل مستخدم جديدMagneto-transport measurements on Nd$_{1.83}$Ce$_{0.17}$CuO$_{4pmdelta}$ thin films
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Nd$_{2-x}$Ce$_x$CuO$_{4pmdelta}$ (NCCO) epitaxial thin films have been deposited on (100) SrTiO$_3$ substrates by DC sputtering technique in different atmosphere. The as-grown samples show different dependence of the in-plane resistivity at low temperature, when they are grown in pure argon atmosphere or in oxygen. Moreover, an unusual behaviour is also found when transport takes place in the presence of an external magnetic field. It is commonly accepted that the higher anisotropic properties of NCCO crystalline cell with respect to the hole doped YBCO and LSCO and the electric conduction mainly confined in the CuO$_2$ plane, strongly support the two-dimensional (2D) character of the current transport in this system. Results on the temperature dependence of the resistance, as well as on the magnetoresistance and the Hall coefficient, obtained on epitaxial NCCO thin films in the over-doped region ($xge0.15$) of the phase diagram are presented and discussed.
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We find an unambiguous relationship between disorder-driven features in the temperature dependence of the resistance and the behavior, as functions of the temperature, of the parameters necessary to describe some of the relaxation processes in the ph
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