Frequency-domain magnetic-resonance spectroscopic investigations of the magnetization dynamics inMn12Acsingle crystals

Abstract

A comprehensive spectroscopic study of the magnetization relaxation of Mn 12 Ac is presented. The single crystalline samples are investigated as a function of magnetic field and temperature using frequency-domain magnetic-resonance spectroscopy. The magnetization relaxation is followed in real-time by recording spectra as a function of delay time. The experiments are performed both in the absence of a magnetic field and in external fields either parallel ͑Faraday geometry͒ or perpendicular ͑Voigt geometry͒ to the direction of radiation. The relaxation rates obtained from spectral fits correspond well to those obtained from magnetometric measurements. The results exhibit clear signatures of quantum tunneling of the magnetization. The influence of D strain and internal dipolar fields is observed.

Inelastic neutron scattering and frequency-domain magnetic resonance studies ofS=4andS=12Pieper1, Guidi2, Carretta3 et al. 2010Phys. Rev. BSelf Cite211160View full textAdd to dashboardCite

“…This can be tentatively attributed to the presence of low-lying excited states as observed previously for Mn 12 Ac. 29 To determine the energy of excited spin states and identify the origin of the lowfrequency resonances we resorted to INS, the technique of choice to directly access intermultiplet excitations.…”

Frequency domain magnetic resonance and magnetic circular dichroism studies on Ni4 cubane molecular nanomagnets: A magnetic anisotropy investigation

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