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arXiv · 2610.08081

Reflection of forward volume exchange spin waves at ferromagnetic junctions interpreted via continuity of angular momentum density flux

Luis Sánchez-Tejerina·Luis M. Moreno-Ramírez·Óscar Alejos Ducal
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Abstract

Magnonics investigates the dynamic excitations of magnetically ordered media, known as spin waves, and their application in functionalized devices. To efficiently control spin wave based devices minimizing losses and interferences from unwanted reflections, a clear picture of the scattering mechanism is needed. Here, we focus on the reflection of spin waves produced at the interface between two ferromagnetic media. We show that it is possible to understand the reflection mechanism based on the continuity of the angular momentum density flux. This constraint allows us to analytically compute the reflection coefficient and the stationary wave envelope in the first medium, as well as the damped propagation in the second. In addition, the analytical expressions are compared with full micromagnetic simulations, showing excellent agreement.

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Luis Sánchez-Tejerina, Luis M. Moreno-Ramírez, Óscar Alejos Ducal. 2026-10-06. Reflection of forward volume exchange spin waves at ferromagnetic junctions interpreted via continuity of angular momentum density flux. https://arxiv.org/abs/2610.08081

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