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arXiv · 1403.2544

Spin reversal in Fe8 under fast pulsed magnetic fields

S. N. Jammalamadaka·J. Vanacken·V. V. Moshchalkov·Saül Vélez·J. Tejada·Ferran Macià
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Abstract

We report measurements on magnetization reversal in the Fe$_8$ molecular magnet using fast pulsed magnetic fields of 1.5 kT/s and in the temperature range of 0.6-4.1 K. We observe and analyze the temperature dependence of the reversal process, which involves in some cases several resonances. Our experiments allow observation of resonant quantum tunneling of magnetization up to a temperature of $\sim$ 4 K. We also observe shifts of the resonance fields in temperature that suggest the emergence of a thermal instability---a combination of spin reversal and self-heating that may result in a magnetic deflagration process. The results are mainly understood in the framework of thermally-activated quantum tunneling transitions in combination with emergence of a thermal instability.

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S. N. Jammalamadaka, J. Vanacken, V. V. Moshchalkov, Saül Vélez, J. Tejada, Ferran Macià. 2014-03-11. Spin reversal in Fe8 under fast pulsed magnetic fields. https://arxiv.org/abs/1403.2544

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