Double-spin-flip resonance of rhodium nuclei at positive and negative spintemperatures

Citation
Jt. Tuoriniemi et al., Double-spin-flip resonance of rhodium nuclei at positive and negative spintemperatures, PHYS REV L, 84(2), 2000, pp. 370-373
Citations number
18
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
84
Issue
2
Year of publication
2000
Pages
370 - 373
Database
ISI
SICI code
0031-9007(20000110)84:2<370:DRORNA>2.0.ZU;2-9
Abstract
Sensitive SQUID-NMR measurements were used to study the mutual interactions in the highly polarized nuclear-spin system of rhodium metal. The dipolar coupling gives rise to a weak double-spin-flip resonance. The observed freq uency shifts allow deducing separately the dipolarlike contribution and the isotropic exchange term. For the first time, such measurements were extend ed to negative absolute temperatures as well. We find an effective dipolar moment 0.10 mu(N) of which about 15% is attributed to a conduction electron mediated pseudodipolar interaction. The isotropic exchange is described by R = -0.9 +/- 0.1.