Abstract
The recently studied material FeCrAs exhibits a surprising combination of experimental signatures, with metallic, Fermi-liquid-like specific heat but resistivity showing strong nonmetallic character. The sublattice posseses local magnetic moments, in the form of stacked (distorted) kagome lattices. Despite the high degree of magnetic frustration, antiferromagnetic order develops below suggesting the nonmagnetic sublattice may play a role in stabilizing the ordering. From the material properties we propose a microscopic Hamiltonian for the low-energy degrees of freedom, including the nonmagnetic sublattice, and study its properties using slave-rotor mean-field theory. Using this approach we find a spin-liquid phase on the sublattice, which survives even in the presence of the magnetic sublattice. Finally, we suggest that the features of FeCrAs can be qualitatively explained by critical fluctuations in the nonmagnetic Fe sublattice due to proximity to a metal-insulator transition.
2 More- Received 18 July 2011
DOI:https://doi.org/10.1103/PhysRevB.84.104448
©2011 American Physical Society