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Field-induced quasi-particle coherence effects in certain small magnets

S. E. Barnes
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Abstract

Small ferromagnets and anti-ferromagnets with an easy-plane anisotropy have a ground to first excited state (tunnel) splitting which is quasi-periodic in the magnitude of a field applied perpendicular to a principal anisotropy axis. The associated oscillations in thermodynamic quantities might be used to prove the existence of a coherent ground state even when the tunnel splitting itself cannot be directly detected.

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S. E. Barnes. 1997-10-28. Field-induced quasi-particle coherence effects in certain small magnets. https://arxiv.org/abs/cond-mat/9710302

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