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The V15 molecule, a multi-spin two-level system: adiabatic LZS transition with or without dissipation and Kramers theorem

B. Barbara·I. Chiorescu·W. Wernsdorfer·H. Boegge·A. Mueller
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Abstract

The so-called V15 molecule is formed of 15 spins 1/2 antiferromagnetically coupled. The resultant spin is equal to 1/2. Contrary to what is expected at first sight, this half-integer spin is gapped. We show that this is a consequence of the multi-spin character of the molecule. Time reversal symmetry (Kramers theorem) is preserved due to the existence of a groundstate degeneracy larger than 2. Magnetization experiments have been performed at different temperatures, sweeping-field rates and couplings with the cryostat. Their interpretation in terms of the Landau-Zener-Stuckelberg model gives evidence for adiabatic LZS spin reversal with and without dissipation.

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B. Barbara, I. Chiorescu, W. Wernsdorfer, H. Boegge, A. Mueller. 2002-05-08. The V15 molecule, a multi-spin two-level system: adiabatic LZS transition with or without dissipation and Kramers theorem. https://doi.org/10.1143/ptps.145.357

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