We report the observation of superconductivity in La3Ni4P4O2 at 2.2 K. The layer stacking in this compound results in an asymmetric distribution of charge reservoir layers around the Ni2P2 planes. The estimated Wilson ratio, Rw ~ 5, indicates the presence of a strongly enhanced normal state susceptibility, but many of the basic superconducting characteristics are conventional. The estimated electronic contribution to the specific heat, gamma ~ 6.2 mJ mol-Ni^-1K^-2, is about 2/3 of that found in layered nickel borocarbide superconductors.
@article{arxiv.0808.1557,
title = {Superconductivity at 2.2K in La3Ni4P4O2},
author = {T. Klimczuk and T. M. McQueen and A. J. Williams and Q. Huang and F. Ronning and E. D. Bauer and J. D. Thompson and M. A. Green and R. J. Cava},
journal= {arXiv preprint arXiv:0808.1557},
year = {2009}
}
Comments
Updated to reflect final version. Added journal reference