Please use this identifier to cite or link to this item:
|Thermally activated and field-tuned tunneling in Mn12Ac studied by ac magnetic susceptibility
|Luis Vitalla, Fernando
Fernández, J. F.
Tejada Palacios, Javier
Hernández Ferràs, Joan Manel
Ziolo, R. F.
|The American Physical Society
|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.
|Reproducció digital del document publicat en format paper, proporcionada per PROLA i http://dx.doi.org/10.1103/PhysRevB.55.11448
|It is part of:
|Physical Review B, 1997, vol. 55, núm. 17, p. 11448-11456.
|Appears in Collections:
|Articles publicats en revistes (Física de la Matèria Condensada)
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.