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arXiv · 0811.3439

A novel non-Fermi-liquid state in the iron-pnictide FeCrAs

W. Wu·A. McCollam·I. Swainson·P. M. C. Rourke·D. G. Rancourt·S. R. Julian
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Abstract

We report transport and thermodynamic properties of stoichiometric single crystals of the hexagonal iron-pnictide FeCrAs. The in-plane resistivity shows an unusual "non-metallic" dependence on temperature T, rising continuously with decreasing T from ~ 800 K to below 100 mK. The c-axis resistivity is similar, except for a sharp drop upon entry into an antiferromagnetic state at T_N 125 K. Below 10 K the resistivity follows a non-Fermi-liquid power law, rho(T) = rho_0 - AT^x with x<1, while the specific heat shows Fermi liquid behaviour with a large Sommerfeld coefficient, gamma ~ 30 mJ/mol K^2. The high temperature properties are reminiscent of those of the parent compounds of the new layered iron-pnictide superconductors, however the T -> 0 properties suggest a new class of non-Fermi liquid.

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W. Wu, A. McCollam, I. Swainson, P. M. C. Rourke, D. G. Rancourt, S. R. Julian. 2008-11-20. A novel non-Fermi-liquid state in the iron-pnictide FeCrAs. https://doi.org/10.1209/0295-5075/85/17009

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