English

A Model for the Schottky Anomaly in Metallic $Nd_{2-y}Ce_{y}CuO_{4}$

Strongly Correlated Electrons 2009-10-31 v2 Superconductivity

Abstract

We present a simple model for the doped compound Nd2yCeyCuO4Nd_{2-y}Ce_{y}CuO_{4}, in order to explain some recent experimental results on the latter. Within a Hartree-Fock context, we start from an impurity Anderson-like model and consider the magnetic splitting of the NdNd-4f4f ground state Kramers doublet due to exchange interactions with the ordered CuCu moments. Our results are in very good agreement with the experimental data, yielding a Schottky anomaly peak for the specific heat that reduces its amplitude, broadens and shifts to lower temperatures, upon CeCe doping. For overdoped compounds at low temperatures, the specific heat behaves linearly and the magnetic susceptibility is constant. A smooth transition from this Fermi liquid like behavior ocurrs as temperature is increased and at high temperatures the susceptibility exhibits a Curie-like behavior. Finally, we discuss some improvements our model is amenable to incorporate.

Keywords

Cite

@article{arxiv.cond-mat/9807337,
  title  = {A Model for the Schottky Anomaly in Metallic $Nd_{2-y}Ce_{y}CuO_{4}$},
  author = {R. E. Lagos and A. C. M. Stein-Barana and G. G. Cabrera},
  journal= {arXiv preprint arXiv:cond-mat/9807337},
  year   = {2009}
}

Comments

7 pages, 5 figures, and 13 references