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

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 نشر من قبل Lloyd Lumata
 تاريخ النشر 2010
  مجال البحث فيزياء
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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 4emph{p}- and Ti 3emph{d}-band contribution to the density of states at the Fermi level in the studied compounds.

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