We report on the manipulation of magnetization by femtosecond laser pulses in a periodic array of cylindrical nickel nanoparticles. By performing experiments at different wavelengths, we show that the excitation of collective surface plasmon resonances triggers demagnetization in zero field or magnetic switching in a small perpendicular field. Both magnetic effects are explained by plasmon-induced heating of the nickel nanoparticles to their Curie temperature. Model calculations confirm the strong correlation between the excitation of surface plasmon modes and laser-induced changes in magnetization.

中文翻译：

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镍纳米颗粒阵列中等离子体诱导的退磁和磁开关

我们报告了在圆柱形镍纳米粒子的周期性阵列中通过飞秒激光脉冲操纵磁化。通过在不同波长下进行实验，我们表明集体表面等离子体共振的激发会触发零场中的退磁或小垂直场中的磁切换。这两种磁效应都可以通过等离子激元将镍纳米颗粒加热到其居里温度来解释。模型计算证实了表面等离子体模式的激发与激光诱导的磁化变化之间的强相关性。