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arXiv · 0709.0684

Muon spin rotation studies of spin dynamics at avoided level crossings in LiY0.998Ho0.002F4

M. J. Graf·J. Lago·A. Lascialfari·A. Amato·C. Baines·S. R. Giblin·J. S. Lord·A. M. Tkachuk·B. Barbara
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Abstract

We have studied the Ho3+ spin dynamics for LiY0.998Ho0.002F4 through the positive muon (mu+) transverse field depolarization rate lambda_TF as a function of temperature and magnetic field. We find sharp reductions in lambda_TF(H) at fields of 23, 46 and 69 mT, for which the Ho3+ ion system has field-induced (avoided) level crossings. The reduction scales with calculated level repulsions, suggesting that mu+ depolarization by slow fluctuations of non-resonant Ho3+ spin states is partially suppressed when resonant tunneling opens new fluctuation channels at frequencies much greater than the muon precession frequency.

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M. J. Graf, J. Lago, A. Lascialfari, A. Amato, C. Baines, S. R. Giblin, J. S. Lord, A. M. Tkachuk, B. Barbara. 2007-09-05. Muon spin rotation studies of spin dynamics at avoided level crossings in LiY0.998Ho0.002F4. https://doi.org/10.1103/physrevlett.99.267203

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