推迟模式下侧向feni超晶格体极化子禁带宽度研究 study on forbidden bandwidth of bulk polaron in retarded modes of lateral feni superlattice.pdfVIP

研究·分析·实验 推迟模式下侧向Fe/Ni 超晶格体极化子禁带宽度研究 1 1 1 1 2 刘艳芬 ，刘晓华 ，孙为民 ，刘晓军 ，林方婷 (1. 齐齐哈尔大学 理学院 物理系，黑龙江齐齐哈尔 161006； 2. 上海师范大学 物理系，上海 200235) 摘 要：基于等效介质理论计算了半无限侧向 Fe/Ni 体系超晶格的体模式，通过对体极化子禁带宽度的讨 论给出了自旋波在该体系下传播区域的改变。外场较小时磁性层的磁比例因子与外场对禁带宽度的影响规律性 较强，Ni 层越厚、外场越大禁带宽度越大。外场增大使趋肤效应与涡流损耗效应增强，导致自旋波衰减，禁带 宽度变化情况复杂化。讨论结果与J.Barnas 利用传输矩阵方法算出的磁性/非磁性超晶格推迟模式的体极化子的 色散曲线很相似。对比发现，等效介质理论更具简便性，在所研究体系中第二种磁性介质的饱和磁化强度趋于0 时即为J.Barnas 的磁性/非磁性超晶格。 关键词：Fe/Ni 体系超晶格；推迟模式；禁带宽度；体极化子 中图分类号：O482.54 文献标识码：A 文章编号：1001-3830(2013)05-0015-04 Study on forbidden bandwidth of bulk polaron in retarded modes of lateral Fe/Ni superlattice 1 1 1 1 2 LIU Yan-fen , LIU Xiao-hua , SUN Wei-min , LIU Xiao-jun , LIN Fang-ting 1. Department of Physics, Qiqihar University, Qiqihar 161006, China; 2. Department of Physics, Shanghai Normal University, Shanghai 200235, China Abstract ：Based on equivalent medium theory, body model of semi-infinite lateral Fe/Ni system superlattice was calculated. By discussion of forbidden band width of body polaron transmission area change of spin wave in the system is given. Under lower field the magnetic scale factor of magnetic layer and the field has stronger influence on the forbidden band width, or thicker Ni layer and higher applied field result in wider forbidden band width. Field increase enhance the skin effect and eddy current loss, leading to spin wave attenuation and complication of forbidden band width changes. The results is in accordance with the body polaron dispersion curve of the magnetic/nonmagnet