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Suppression of Quantum Phase Interference in Molecular Magnets Fe₈ with Dipolar-Dipolar Interaction

Zhi-De Chen·J. -Q. Liang·Shun-Qing Shen
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Abstract

Renormalized tunnel splitting with a finite distribution in the biaxial spin model for molecular magnets is obtained by taking into account the dipolar interaction of enviromental spins. Oscillation of the resonant tunnel splitting with a transverse magnetic field along the hard axis is smeared by the finite distribution which subsequently affects the quantum steps of hysteresis curve evaluated in terms of the modified Landau-Zener model of spin flipping induced by the sweeping field. We conclude that the dipolar-dipolar interaction drives decoherence of quantum tunnelling in molcular magnets Fe₈, which explains why the quenching points of tunnel spliting between odd and even resonant tunnelling predcited theoretically were not observed experimentally.

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Zhi-De Chen, J. -Q. Liang, Shun-Qing Shen. 2002-08-01. Suppression of Quantum Phase Interference in Molecular Magnets Fe₈ with Dipolar-Dipolar Interaction. https://doi.org/10.1103/physrevb.66.092401

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