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تسجيل مستخدم جديدMagneto-transport properties governed by the antiferromagnetic fluctuations in heavy fermion superconductor CeIrIn$_{5}$
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In quasi-two dimensional Ce(Ir,Rh)In$_5$ system, it has been suggested that the phase diagram contains two distinct domes with different heavy fermion superconducting states. We here report the systematic pressure dependence of the electron transport properties in the normal state of CeRh$_{0.2}$Ir$_{0.8}$In$_{5}$ and CeIrIn$_{5}$, which locates in first and second superconducting dome, respectively. We observed non-Fermi liquid behavior at low temperatures in both compounds, including non-quadratic $T-$dependence of the resistivity, large enhancement of the Hall coefficient, and the violation of the Kohlers rule in the magnetoresistance. We show that the cotangent of Hall angle $cot Theta_H$ varies as $T^2$, and the magnetoresistance is quite well scaled by the Hall angle as $Delta rho_{xx}/rho_{xx}propto tan^2Theta_H$. The observed transport anomalies are common features of Ce$M$In$_{5}$ ($M$=Co, Rh, and Ir) and high-$T_c$ cuprates, suggesting that the anomalous transport properties observed in CeIrIn$_{5}$ are mainly governed by the antiferromagnetic spin fluctuations, not by the Ce-valence fluctuations which has been proposed to be the possible origin for the second superconducting dome.
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