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Magnetic, electrical resistivity, heat-capacity and thermopower anomalies in CeCuAs2

Kausik Sengupta·E. V. Sampathkumaran·T. Nakano·M. Hedo·M. Abliz·N. Fujiwara·Y. Uwatoko·S. Rayaprol·K. Shigetoh·T. Takabatake·Th. Doert·J. PF. Jemetio
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Abstract

The results of magnetic susceptibility, electrical resistivity ($ρ$), 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 $ρ$ behavior is notable in the sense that (i) the temperature (T)-coefficient of $ρ$ is negative in the entire range of measurement (45 mK to 300 K) with large values of $ρ$, while S behavior is typical of metallic Kondo lattices, and (ii) $ρ$ 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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Kausik Sengupta, E. V. Sampathkumaran, T. Nakano, M. Hedo, M. Abliz, N. Fujiwara, Y. Uwatoko, S. Rayaprol, K. Shigetoh, T. Takabatake, Th. Doert, J. PF. Jemetio. 2004-05-27. Magnetic, electrical resistivity, heat-capacity and thermopower anomalies in CeCuAs2. https://doi.org/10.1103/physrevb.70.064406

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