Original scientific paper
Termička relaksacija i kvantno tuneliranje magnetizacije u Mn12-acetatu
Damir Pajić
; Department of Physics, Faculty of Science, University of Zagreb, Bijeni cka c. 32, HR-10000 Zagreb, Croatia
Krešo Zadro
; Department of Physics, Faculty of Science, University of Zagreb, Bijeni cka c. 32, HR-10000 Zagreb, Croatia
Tomislav Friščić
; Department of Chemistry, Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, Ul. kralja Zvonimira 8, HR-10000 Zagreb, Croatia
Nenad Judaš
; Department of Chemistry, Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, Ul. kralja Zvonimira 8, HR-10000 Zagreb, Croatia
Ernest Meštrović
; Department of Chemistry, Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, Ul. kralja Zvonimira 8, HR-10000 Zagreb, Croatia
Abstract
Mjerili smo ovisnost magnetskog momenta m sintetiziranog molekulskog magneta Mn12-acetat o temperaturi T i magnetskom polju H pomoću SQUID magnetometra. Ispod tzv. temperature kočenja TB (≈ 3.6 K pri H = 0) primijetili smo razdvajanje krivulja m(T) za uzorak hlađen bez polja (ZFC) i hlađen u polju (FC). Mjerenja vremenske relaksacije m pokazuju da m teži istim vrijednostima s jednakim relaksacijskim vremenima (≈ 560 s na 3 K) za oba procesa, ZFC i FC. Narečeno ukazuje na zamrzavanje spinova ispod temperature kočenja TB (≈ 3.5 K) i jednočestičnu prirodu procesa u istraživanom temperaturnom području (2 K
Keywords
Hrčak ID:
301017
URI
Publication date:
3.10.1999.
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