Spin fluctuations, magnetic long-range order and Fermi surface gapping in NaxCoO2
Abstract
In this study an extended low energy phase diagram for NaxCoO2 is experimentally established with emphasis on the high x range. It is based on systematic heat capacity studies on both polycrystalline and single crystalline samples and on uSR measurements. Main features are the existence of mass enhancement, spin fluctuations without long-range order, and magnetic order with associated Fermi surface gapping. The latter is seen in the electronic density of states (DOS) and suppression of nuclear specific heat. While there is agreement between the band structure and the low energy DOS in the low x range, in the high x range (x > 0.6) the thermodynamically determined DOS is approximately three times that deduced from the angle-resolved photoemission spectroscopy (ARPES)-measured band dispersion or local-density approximation (LDA) calculations.
Cite
@article{arxiv.0808.1697,
title = {Spin fluctuations, magnetic long-range order and Fermi surface gapping in NaxCoO2},
author = {T. F. Schulze and M. Bruehwiler and P. S. Haefliger and S. M. Kazakov and Ch. Niedermayer and K. Mattenberger and J. Karpinski and B. Batlogg},
journal= {arXiv preprint arXiv:0808.1697},
year = {2009}
}
Comments
9 pages, 5 figures