Quantum relaxation of magnetisation in magnetic particles

@article{Prokofev1996QuantumRO,
  title={Quantum relaxation of magnetisation in magnetic particles},
  author={Nikolay Prokof'ev and Philip C. E. Stamp},
  journal={Journal of Low Temperature Physics},
  year={1996},
  volume={104},
  pages={143-209}
}
At temperatures below the magnetic anisotropy energy, monodomain magnetic systems (small particles, nanomagnetic devices, etc.) must relax quantum mechanically-thermal activation is ineffective. The discrete nature of the spectrum is important. This quantum relaxation must be mediated by the coupling to both nuclear spins and phonons (and electrons if either particle or substrate is conducting).We analyze the effect of each of these couplings, and then combine them to get results for the… 
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