Carregant...
Miniatura

Tipus de document

Article

Versió

Versió publicada

Data de publicació

Tots els drets reservats

Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/10659

Thermally activated and field-tuned tunneling in Mn12Ac studied by ac magnetic susceptibility

Títol de la revista

Director/Tutor

ISSN de la revista

Títol del volum

Resum

The magnetic ac susceptibility x of oriented Mn12Ac crystallites has been measured as a function of temperature, field, and frequency. The field has been applied at different values of the angle u with respect to the sample easy axis. For T55 K, the isothermal and adiabatic x limits have been determined as a function of field. For u50° and intermediate frequencies, Lorentzian-shaped peaks have been observed at magnetic field values Hn5nH1 with n50, 1, and 2 where H154.1 kOe. As u increases these maxima shift to higher fields, that satisfy Hncosu5const, and decrease in amplitude. The relaxation time t 1 follows Arrhenius’ law with respect to temperature and decreases sharply at H5Hn . The observed phenomenology unambiguously proves the existence of field-tuned tunneling between excited magnetic states which are thermally populated. At 5 K, the effective activation energy and the spin states involved in the tunneling process have been obtained.

Citació

Citació

LUIS VITALLA, Fernando, BARTOLOMÉ, J., FERNÁNDEZ, J. f., TEJADA PALACIOS, Javier, HERNÁNDEZ FERRÀS, Joan manel, ZHANG, Xixiang, ZIOLO, R. f.. Thermally activated and field-tuned tunneling in Mn12Ac studied by ac magnetic susceptibility. _Physical Review B_. 1997. Vol. 55, núm. 17, pàgs. 11448-11456. [consulta: 25 de gener de 2026]. ISSN: 0163-1829. [Disponible a: https://hdl.handle.net/2445/10659]

Exportar metadades

JSON - METS

Compartir registre