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arXiv · 2201.13074

Nuclear spin-lattice relaxation studies of Cu$_{2}$O

Yutaka Itoh
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Abstract

We report the $^{63}$Cu and $^{65}$Cu nuclear spin-lattice relaxation rate measurements of cuprous oxide Cu$_2$O in a zero field Cu nuclear quadrupole resonance at $T$ = 77$-$325 K. From the detailed isotopic measurements of the relaxation rates, we successfully estimated a finite magnetic relaxation rate $^{63}W_M$ and a predominant nuclear quadrupole relaxation rate $^{63}W_Q$. $^{63}W_Q$ changed as $T^{2.1}$, while $^{63}W_M$ changed as $T^{1.6}$ or $T^{\beta}\mathrm{exp}(-\it\Delta/T)$ with $\beta$ = 0.6(3) and $\it\Delta$ = 190(62) K. The nuclear spin scattering process due to a non-degenerate Fermi gas was discussed as a possible candidate of the magnetic relaxation.

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Yutaka Itoh. 2022-01-31. Nuclear spin-lattice relaxation studies of Cu$_{2}$O. https://doi.org/10.1103/physrevb.105.094429

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