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The quantum dynamics of atomic magnets, co-tunneling and dipolar-biased tunneling

R. Giraud·A. M. Tkachuk·B. Barbara
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Abstract

Multi-spins tunneling cross-relaxations in an ensemble of weakly-coupled Ho$^{3+}$ ions, mediated by weak anisotropic dipolar interactions, can be evidenced by ac-susceptibility measurements in a high temperature regime. Based on a four-body representation, including the rare-earth nuclear spin, two-ions tunneling mechanisms can be attributed to both dipolar-biased tunneling and co-tunneling processes. The co-reversal involving entangled pairs of magnetic moments is discussed with a particular emphasis, giving new evidences to elucidate the many-body quantum dynamics.

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R. Giraud, A. M. Tkachuk, B. Barbara. 2003-07-16. The quantum dynamics of atomic magnets, co-tunneling and dipolar-biased tunneling. https://doi.org/10.1103/physrevlett.91.257204

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