论文标题
超快的所有光学磁化控制宽带Terahertz自旋波产生
Ultrafast All Optical Magnetization Control for Broadband Terahertz Spin Wave Generation
论文作者
论文摘要
Terahertz自旋波可以通过飞秒激光脉冲对磁化的全光操作产生点播。在这里，我们提出了一个能量平衡模型，该模型解释了从激光脉冲到电子浴的能量转移速率，并与声子，自旋和五种不同的磁性金属薄膜的磁化：铁，钴，镍，gadolin和ni $ _ {2} $ _ {2} $ MNSN HEUSLER ALLOY。基于其curie温度（T $ _ {C} $），在金属磁性薄膜中出现了两种类型的短暂磁化动力学：类型I（Fe，Co和Ni，带有T $ _ {C} $>室温，RT）和II型II胶片（GD和Ni $ _ {2} $ _ {2} $ MNSN，c $} $ _ {我们研究了激光通量和脉冲宽度对单高斯激光脉冲的影响以及金属膜厚度对磁化动力学的影响。频谱动力学表明，通过对这些纳米膜中的磁化的全光操作，可以产生宽带自旋波最多24 THz。
Terahertz spin waves could be generated on-demand via all-optical manipulation of magnetization by femtosecond laser pulse. Here, we present an energy balance model, which explains the energy transfer rates from laser pulse to electron bath coupled with phonon, spin, and magnetization of five different magnetic metallic thin films: Iron, Cobalt, Nickel, Gadolinium and Ni$_{2}$MnSn Heusler alloy. Two types of transient magnetization dynamics emerge in metallic magnetic thin films based on their Curie temperatures (T$_{C}$): type I (Fe, Co, and Ni with T$_{C}$ > room temperature, RT) and type II films (Gd and Ni$_{2}$MnSn with T$_{C}$ $\approx$ RT). We study the effect of laser fluence and pulse width for single Gaussian laser pulses and the effect of metal film thickness on magnetization dynamics. Spectral dynamics show that broadband spin waves up to 24 THz could be generated by all-optical manipulation of magnetization in these nanofilms.
