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Resonant quantum coherence of magnetization at excited states in nanospin systems with different crystal symmetries

Jia-Lin Zhu·Rong Lu·Su-Pen Kou·Hui Hu·Bing-Lin Gu
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Abstract

The quantum interference effects induced by the Wess-Zumino term, or Berry phase are studied theoretically in resonant quantum coherence of magnetization vector between degenerate excited states in nanometer-scale single-domain ferromagnets in the absence of an external magnetic field. By applying the periodic instanton method in the spin-coherent-state path integral, we evaluate the low-lying tunnel splittings between degenerate excited states of neighboring wells. And the low-lying energy level spectrum of m-th excited states are obtained with the help of the Bloch theorem in one-dimensional periodic potential.

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Jia-Lin Zhu, Rong Lu, Su-Pen Kou, Hui Hu, Bing-Lin Gu. 2000-05-19. Resonant quantum coherence of magnetization at excited states in nanospin systems with different crystal symmetries. https://doi.org/10.1007/s100510070210

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