Susceptibility and relaxation measurements on rhodium metal at positive and negative spin temperatures in the Nanokelvin range
In: Journal of low temperature physics, Jg. 98 (1995), Heft 5-6, S. 449-487
Online
academicJournal
- print, 72 ref
Zugriff:
We have measured the susceptibility of polycrystalline rhodium foils, down to nuclear spin temperatures T = 280 pK and «up» to T = -750 pK. At T > 0, the static susceptibility follows the antiferromagnetic Curie-Weiss law with θ = -1.8 ± 0.3 nK. At T < 0, the expected ferromagnetic behavior in the vicinity of T = -0 changes into antiferromgnetic tendency around -6 nK. If only nearest and next nearest neighbor interactions are assumed, our data yield Jnn/h = -17 ± 3 Hz and Jnnn/h = 10 ± 3 Hz for the exchange interaction coefficients. We have also investigated the field and polarization dependence of the spin-lattice relaxation time τ1 at positive and negative nanokelvin temperatures; surprisingly τ1 is longer when T < 0. In fields below 1 mT, the Korringa constant shows a strong decrease, which becomes more pronounced as the conduction electron temperature decreases. Observed behavior is consistent with conduction electrons scattering from magnetic impurities, provided that the impurity-induced contribution to spin-lattice relaxation is proportional to the inverse of the nuclear spin temperature in small fields.
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Susceptibility and relaxation measurements on rhodium metal at positive and negative spin temperatures in the Nanokelvin range
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Autor/in / Beteiligte Person: | VUORINEN, R. T ; HAKONEN, P. J ; YAO, W ; LOUNASMAA, O. V |
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Zeitschrift: | Journal of low temperature physics, Jg. 98 (1995), Heft 5-6, S. 449-487 |
Veröffentlichung: | Heidelberg: Springer, 1995 |
Medientyp: | academicJournal |
Umfang: | print, 72 ref |
ISSN: | 0022-2291 (print) |
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