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arXiv · 2010.14981

Strong coupling of quantized spin waves in ferromagnetic bilayers

Zhizhi Zhang·Huanhuan Yang·Zhenyu Wang·Yunshan Cao·Peng Yan
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Abstract

We formulate a strong-coupling theory for perpendicular standing spin waves (PSSWs) in ferromagnetic bilayers with the interlayer exchange coupling (IEC). Employing the Hoffmann boundary condition and the energy-flow continuity across the interface, we show that the PSSWs are still quantized but with non-integral quantum numbers, in sharp contrast to that of a single layer. The magnon-magnon coupling is characterized by the spectrum splitting which is linear with the IEC in the weak-coupling region, but getting saturated in the strong-coupling limit. Analytical predictions are verified by full micromagnetic simulations with good agreement.

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Zhizhi Zhang, Huanhuan Yang, Zhenyu Wang, Yunshan Cao, Peng Yan. 2020-10-28. Strong coupling of quantized spin waves in ferromagnetic bilayers. https://doi.org/10.1103/physrevb.103.104420

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