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Two-body tunnel transitions in a Mn4 Single-Molecule Magnet

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 نشر من قبل Wernsdorfer Wolfgang
 تاريخ النشر 2003
  مجال البحث فيزياء
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The one-body tunnel picture of single-molecule magnets (SMMs) is not always sufficient to explain the measured tunnel transitions. An improvement to the picture is proposed by including also two-body tunnel transitions such as spin-spin cross-relaxation (SSCR) which are mediated by dipolar and weak superexchange interactions between molecules. A Mn4 SMM is used as a model system. At certain external fields, SSCRs lead to additional quantum resonances which show up in hysteresis loop measurements as well defined steps.



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