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Landau-Zener tunneling with many-body quantum effects in crystals of molecular magnets

Li-Bin Fu·Shi-Gang Chen·Bambi Hu
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Abstract

We present a quantum interpretation of the heights in hysteresis of $Fe_{8}$ molecule at lower temperatures by treating the crystal as an Ising spin system with the dipolar interaction between spins. Then we apply it to two limit cases : rapid and adiabatic regions. Our theoretical analysis is in agreement with the experimental observation in these regions, which indicates that the steps in hysteresis loops of magnetization of Fe$_{8}$ at lower temperatures show a pure quantum process.

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Li-Bin Fu, Shi-Gang Chen, Bambi Hu. 2004-03-16. Landau-Zener tunneling with many-body quantum effects in crystals of molecular magnets. https://doi.org/10.1016/j.physleta.2004.02.015

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