Bulk antiferromagnetism in $\bf Na_{0.82}CoO_2$ single crystals
arXiv:cond-mat/0312376 · doi:10.1103/PhysRevB.69.100410
Abstract
Susceptibility, specific heat, and muon spin rotation measurements on high-quality single crystals of $\rm Na_{0.82}CoO_2$ have revealed bulk antiferromagnetism with Néel temperature $\rm T_N = 19.8 \pm 0.1$ K and an ordered moment perpendicular to the $\rm CoO_2$ layers. The magnetic order encompasses nearly 100% of the crystal volume. The susceptibility exhibits a broad peak around 30 K, characteristic of two-dimensional antiferromagnetic fluctuations. The in-plane resistivity is metallic at high temperatures and exhibits a minimum at $\rm T_N$.
published version