nd - m at . m es - h al l ] 1 6 Ju l 2 00 3 The quantum dynamics of atomic magnets , co - tunneling and dipolar - biased tunneling
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چکیده
Multi-spins tunneling cross-relaxations in an ensemble of weakly-coupled Ho 3+ ions, mediated by weak anisotropic dipolar interactions, can be ev-idenced 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 tun-neling 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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تاریخ انتشار 2008