大磁化诱导的二次波生成在一个enantiopure奇拉磁体中
Cyrille Train1, Tomohiro Nuida, Ruxandra Gheorghe
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. cyrille.train@grenoble.cnrs.fr
Journal of the American Chemical Society
|November 4, 2009
概括
缺乏中心对称性的状磁铁表现出显著的磁化诱导的第二波生成 (SHG). 这种非线性光学效应在[N(CH(3)) ((n-C(3) H(7)) ((2))) ((C*H(CH(3)) ((C(2) H(5)) [Mn(II) Cr(III) ((ox) ((3)) ]中观察到,超过了线性磁光学反应.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 非线性光学是非线性光学.
- 磁力学 磁力学 是一种
背景情况:
- 对于观察非线性光学现象,如第二波生成 (SHG) 等,中心对称破裂至关重要.
- 螺旋磁性材料提供了探索合自旋-电荷-光子相互作用的独特机会.
- 磁化诱导SHG (MSHG) 是一种对磁性秩序和对称性的敏感探针.
研究的目的:
- 为了研究一个enantiopure性磁体中大量第二波生成 (SHG) 的潜力.
- 描述磁化诱导的SHG (MSHG) 贡献及其对磁场的依赖.
- 分析这个性磁系统中非线性易感度张数的对称性属性.
主要方法:
- 单晶奇拉磁体的合成和特征 [N ((CH ((3)) ((n-C ((3) H ((7)) ((2) ((C*H ((CH ((3)) ((C ((2) H ((5))) ((Mn ((II)) ((Cr ((III)) ((ox)))))) ].
- 作为温度,磁场方向和极化功能的SHG和MSHG的光学测量.
- 基于对称性的非线性灵敏度张量分析,以解释观察到的MSHG效应.
主要成果:
- 吉拉磁体中缺少中心对称性,使得可以观察大量的SHG.
- 显著的MSHG贡献出现在磁性订单温度以下,在磁化逆转时显示出很大的角度转移.
- 观察到的MSHG效应比线性磁光效应大得多.
- 实验性MSHG变异通过对称性分析在偏磁和铁磁阶段都得到了很好的复制.
结论:
- 缺少中心对称性的性磁铁是观测大型MSHG的有希望的平台.
- 这种材料中的MSHG提供了一种灵敏而高效的方法来探测磁性和对称性.
- 这项研究证明了基于对称性的分析对于理解磁性材料中的非线性光学反应的实用性.
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