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arXiv 1910.05099cond-mat.mes-hall
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磁动力学中的Hannay角

Hannay Angles in Magnetic Dynamics

Andreas Rückriegel, R. A. Duine

摘要:

在Hannay为经典可积系统[Journal of Physics A:Mathematical and General { \bf 18},221(1985)]开发的框架内,我们考虑了半经典磁动力学中出现的几何相。这样的几何相位一般被称为汉内角,并且在磁动力学的上下文中,可以作为绝热变化的椭圆率和磁化轴进动的结果而出现。我们阐明了在一个简单的模型与时间相关的各向异性和外部场的单域磁动力学的影响和它们之间的相互作用。随后,我们考虑自旋波和重新推导,从我们的经典方法,一些已知的结果通常被称为磁振子贝里相位。顺便说一句,这些结果被用来解释发生在超流体中的几何相。最后,我们发展了椭圆磁振子的格林函数形式。在这种形式主义,我们认为磁振子输运在介观环,并显示它是如何影响的干涉效应,调谐的Hannay角,结果从一个不同的椭圆。我们的研究结果可能会告知该领域的磁振子,寻求利用自旋波的应用。

英文摘要:

We consider, within the framework developed by Hannay for classical integrable systems [Journal of Physics A: Mathematical and General {\bf 18}, 221 (1985)], the geometric phases that occur in semi-classical magnetic dynamics. Such geometric phases are generically referred to as Hannay angles, and, in the context of magnetic dynamics, may arise as a result of both adiabatically-varying ellipticity and axis of magnetization precession. We elucidate both effects and their interplay for single-domain magnetic dynamics within a simple model with time-dependent anisotropies and external field. Subsequently, we consider spin waves and rederive, from our classical approach, some known results on what is commonly referred to as the magnon Berry phase. As an aside, these results are used to give an interpretation for geometric phases that occur in superfluids. Finally, we develop a Green's function formalism for elliptical magnons. Within this formalism, we consider magnon transport in a mesoscopic ring and show how it is influenced by interference effects that are tuned by the Hannay angle that results from a varying ellipticity. Our results may inform the field of magnonics that seeks to utilize spin waves in applications.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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