AVS 52nd International Symposium
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI+NS-TuM

Invited Paper MI+NS-TuM9
Magnetic Quantum Tunneling and Relaxation in Molecular Magnets

Tuesday, November 1, 2005, 11:00 am, Room 204

Session: Magnetic Nanostructures, Surfaces, and Interfaces
Presenter: L.J. de Jongh, Leiden University, The Netherlands
Authors: L.J. de Jongh, Leiden University, The Netherlands
A. Morello, Leiden University, The Netherlands
F. Luis, Leiden University, The Netherlands
M. Evangelisti, Leiden University, The Netherlands
F. Mettes, Leiden University, The Netherlands
Correspondent: Click to Email
For strongly anisotropic magnetic clusters, like Fe@sub 8@ and Mn@sub 12@-ac, quantum tunneling of the cluster spins below their blocking temperatures T@sub B@ of a few K has been observed by several groups, and is expected to be triggered by the dynamic hyperfine interaction of the cluster spins with their surrounding nuclear spins, as recently predicted by Prokof’ev and Stamp.@footnote 1@ In that model, however, the ensuing relaxation of the electron spins is towards the nuclear spin system, leaving open the question if and at what stage, by which mechanism and at what rates the nuclear and electronic spin systems relax to the lattice phonons. That such phonon relaxation channels are indeed operative even deep in the quantum regime, could be proven unambiguously by our measurements of the specific heat contributions of both nuclear and electronic spin systems at temperatures T<