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arXiv · 1002.3553

$^{77}$Se and $^{63}$Cu NMR studies of the electronic correlations in Cu$_x$TiSe$_2$ ($x=0.05, 0.07$)

L. L. Lumata·K. Y. Choi·J. S. Brooks·A. P. Reyes·P. L. Kuhns·G. Wu·X. H. Chen
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Abstract

We report $^{77}$Se and $^{63}$Cu nuclear magnetic resonance (NMR) investigation on the charge-density-wave (CDW) superconductor Cu$_x$TiSe$_2$ ($x=0.05$ and 0.07). At high magnetic fields where superconductivity is suppressed, the temperature dependence of $^{77}$Se and $^{63}$Cu spin-lattice relaxation rates 1/T_{1}$ follow a linear relation. The slope of $^{77}1/T_{1}$ vs \emph{T} increases with the Cu doping. This can be described by a modified Korringa relation which suggests the significance of electronic correlations and the Se 4\emph{p}- and Ti 3\emph{d}-band contribution to the density of states at the Fermi level in the studied compounds.

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L. L. Lumata, K. Y. Choi, J. S. Brooks, A. P. Reyes, P. L. Kuhns, G. Wu, X. H. Chen. 2010-05-13. $^{77}$Se and $^{63}$Cu NMR studies of the electronic correlations in Cu$_x$TiSe$_2$ ($x=0.05, 0.07$). https://doi.org/10.1088/0953-8984%2F22%2F29%2F295601

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