Time relaxation of interacting single--molecule magnets
arXiv:cond-mat/0508547 · doi:10.1103/PhysRevB.72.094431
Abstract
We study the relaxation of interacting single--molecule magnets (SMMs) in both spatially ordered and disordered systems. The tunneling window is assumed to be, as in Fe8, much narrower than the dipolar field spread. We show that relaxation in disordered systems differs qualitatively from relaxation in fully occupied cubic and Fe_8 lattices. We also study how line shapes that develop in ''hole--digging'' experiments evolve with time t in these fully occupied lattices. We show (1) that the dipolar field h scales as t^p in these hole line shapes and show (2) how p varies with lattice structure. Line shapes are not, in general, Lorentzian. More specifically, in the lower portion of the hole, they behave as (h/t^p)^{(1/p)-1} if h is outside the tunnel window. This is in agreement with experiment and with our own Monte Carlo results.
21 LaTeX pages, 6 eps figures. Submitted to PRB on 15 June 2005. Accepted on 13 August 2005
References in corpus (15)
- Low-Temperature Quantum Relaxation in a System of Magnetic Nanomolecules
- Observation of the distribution of molecular spin states by resonant quantum tunneling of the magnetization
- The effects of nuclear spins on the quantum relaxation of the magnetization for the molecular nanomagnet Fe_8
- Spin quantum tunneling via entangled states in a dimer of exchange coupled single-molecule magnets
- Nuclear spin dynamics in the quantum regime of a single-molecule magnet
- Dipolar interaction and incoherent quantum tunneling: a Monte Carlo study of magnetic relaxation
- Magnetization Process of Single Molecule Magnets at Low Temperatures
- Tunneling of a large spin via hyperfine interactions
- 'Hole-digging' in ensembles of tunneling Molecular Magnets
- Answer to the comment of Chudnovsky: On the square-root time relaxation in molecular nanomagnets
- How systems of single-molecule magnets magnetize at low temperatures
- Nonexponential Relaxation of Magnetization at the Resonant Tunneling Point under a Fluctuating Random Noise
- Comment on "Hole digging in ensembles of tunneling molecular magnets"
- Reply to the Comment on the 'Hole-digging' in ensembles of tunneling molecular magnets
- Magnetic Tunnel Window's Imprint and Beyond
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- Fronts of spin tunneling in molecular magnets
- Dipolar-controlled spin tunneling and relaxation in molecular magnets