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تسجيل مستخدم جديدMagnetic, electrical resistivity, heat-capacity and thermopower anomalies in CeCuAs2
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The results of magnetic susceptibility, electrical resistivity ($rho$), heat-capacity (C) and thermopower (S) measurements on CeCuAs2, forming in ZrCuSi2-type tetragonal structure, are reported. Our investigations reveal that Ce is trivalent and there is no clear evidence for long range magnetic ordering down to 45 mK. The $rho$ behavior is notable in the sense that (i) the temperature (T)-coefficient of $rho$ is negative in the entire range of measurement (45 mK to 300 K) with large values of $rho$, while S behavior is typical of metallic Kondo lattices, and (ii) $rho$ is proportional to T-0.6 at low temperatures, without any influence on the exponent by the application of a magnetic field, which does not seem to classify this compound into hither-to-known non-Fermi liquid (NFL) systems. In contrast to the logarithmic increase known for NFL systems, C/T measured down to 0.5 K exhibits a fall below 2 K. The observed properties of this compound are unusual among Ce systems.
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