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Large-field versus discontinuous instantons in spin orientation tunneling

Anupam Garg·Ersin Kececioglu
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Abstract

Tunnel splitting oscillations in magnetic molecules are reconsidered within the simplest model for the problem, which does not contain fourth order anisotropy. It is shown that at large magnetic field, there is only one instanton, and it is continuous. This is in contrast to the discontinuous instantons that are induced by the fourth order term [Ersin Keçecioğlu and A. Garg, Phys. Rev. Lett. {\bf 88}, 237205 (2002)].

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Anupam Garg, Ersin Kececioglu. 2002-10-11. Large-field versus discontinuous instantons in spin orientation tunneling. https://arxiv.org/abs/cond-mat/0210277

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