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Hysteresis loops and adiabatic Landau-Zener-Stückelberg transitions in the magnetic molecule V$_6$

I. Rousochatzakis·Y. Ajiro·H. Mitamura·P. Kögerler·M. Luban
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Abstract

We have observed hysteresis loops and abrupt magnetization steps in the magnetic molecule V$_6$, where each molecule comprises a pair of identical spin triangles, in the temperature range 1-5 K for external magnetic fields $B$ with sweep rates of several Tesla/ms executing a variety of closed cycles. The hysteresis loops are accurately reproduced using a generalization of the Bloch equation based on direct one-phonon transitions between the instantaneous Zeeman-split levels of the ground state (an $S=1/2$ doublet) of each spin triangle. The magnetization steps occur for $B\approx 0$ and they are explained in terms of adiabatic Landau-Zener-Stückelberg transitions between the lowest magnetic energy levels as modified by inter-triangle anisotropic exchange of order 0.4 K.

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I. Rousochatzakis, Y. Ajiro, H. Mitamura, P. Kögerler, M. Luban. 2005-02-04. Hysteresis loops and adiabatic Landau-Zener-Stückelberg transitions in the magnetic molecule V$_6$. https://doi.org/10.1103/physrevlett.94.147204

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