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Hole-digging in ensembles of tunneling Molecular Magnets

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 نشر من قبل Tupitsyn
 تاريخ النشر 2003
  مجال البحث فيزياء
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The nuclear spin-mediated quantum relaxation of ensembles of tunneling magnetic molecules causes a hole to appear in the distribution of internal fields in the system. The form of this hole, and its time evolution, are studied using Monte Carlo simulations. It is shown that the line-shape of the tunneling hole in a weakly polarised sample must have a Lorentzian lineshape- the short-time half-width $xi_o$ in all experiments done so far should be $sim E_0$, the half-width of the nuclear spin multiplet. After a time $tau_o$, the single molecule tunneling relaxation time, the hole width begins to increase rapidly. In initially polarised samples the disintegration of resonant tunneling surfaces is found to be very fast.

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Reply to the Comment of J.J. Alonso and J.F. Fernandez on the paper Hole-digging in ensembles of tunneling molecular magnets of I.S. Tupitsyn, P.C.E. Stamp and N.V. Prokofev (Phys. Rev. B 69, 132406, (2004)).
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