Spin dynamics in highly polarized silver at negative absolute temperatures

Autor:	R. T. Vuorinen, K. K. Nummila, Pertti Hakonen
Přispěvatelé:	Perustieteiden korkeakoulu, School of Science, Teknillisen fysiikan laitos, Department of Applied Physics, Aalto-yliopisto, Aalto University
Rok vydání:	1992
Předmět:	negative absolute temperatures Physics Spin dynamics Condensed matter physics Spin polarization Transition metal polarized silver Exchange interaction Condensed Matter::Strongly Correlated Electrons spin dynamics
Zdroj:	Physical Review B. 45:2196-2200
ISSN:	1095-3795 0163-1829
DOI:	10.1103/physrevb.45.2196
Popis:	We have studied the spin dynamics of highly polarized silver nuclei at negative absolute temperatures up to inverted polarizations p≃-70%. The measured NMR spectra at B=0.4 and 0.8 mT display a clear inverted suppression-enhancement effect, arising from an interaction between the two spin species, 107Ag and 109Ag. The averaged interaction-field description accounts well for the intensity ratio of the isotopic NMR lines. The frequency difference of the absorption maxima has been used to study the merging and repulsion of the NMR modes at large negative polarizations. At B=0.2 mT, our spectra display only a single exchange-merged line, indicating that the two isotopes act as like spins. The transition from a single NMR line to two separate lines proceeds in a similar fashion as at positive temperatures. No effects attributable to the tendency of ferromagnetic alignment of spins at T
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::460e9edbbe07a87713276d9cf4ae4f9a https://doi.org/10.1103/physrevb.45.2196 Zobrazit plný text záznamu