2003/09/16 by J. F. Fernandez, J. J. Alonso
Physics and Astronomy · #cond-mat
paper · pdf · doi:10.1103/physrevlett.91.047202
published as Phys. Rev. Lett., v91, 047202 (2003) · 5 LaTeX pages, 2 figures. Submitted to Phys. Rev. Lett. on 26 January 2003, accepted on 24 July 2003
arxiv created 2003/09/16 · arxiv updated 2009/12/01
We show that correlations established before quenching to very low temperatures, later drive the magnetization process of systems of single molecule magnets, after a magnetic field is applied at t=0. We also show that in SC lattices, m ∝ sqrt(t), as observed in Fe8, but only for 1+2*log10(hd/hw) time decades, where hd is a nearest neighbor dipolar magnetic field and a spin reversal can occur only if the field on it is within (-hw,hw). However, the sqrt(t) behavior is not universal. For BCC and FCC lattices, m ∝ tp, but p ≃ 0.7. The value to which m finally levels off is also given.