Photo-induced magnetic phase transition in spin crossover complexes

自旋交叉复合物中的光致磁相变

基本信息

批准号：
11215202
负责人：
MINAMI Fujio
金额：
$ 26.37万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

Photowithching process between low- and high-spin states in is investigated in spin crossover materials, such as spin crossover complexes and semimagnetic semiconductors. The outline of the achieved results is shown as follows.(1) Photo-induced magnetic phase transition in spin crossover complexesDetails of the photo-induced magnetic phase transition in Fe^<2+> spin crossover complexes were investigated by measuring absorption spectrum and magnetic susceptibility. In the photoswithing process between low- and high-spin states, nonlinear characteristics such as thresholdlike behavior, incubation period, and phase separation have been observed. These results demonstrate that the cooperative intersystem crossing mediated by spin-lattice interaction plays a key role in driving process of a new class of nonequilibrium phenomena. In addition, it turned out that this photo-induced magnetic phase transition process was greatly influenced by an external magnetic field.(2) Photo-induced magnetic phase transition in semimagnetic semiconductorsTime-resolved Magneto-photoluminescence experiments were carried out in a semimagnetic semiconductor Cd _<0.9>Mn_<0.1>Te with varing exciton density. A reduction of the Zeeman shift and the binding energy of magnetic polaron is observed. The spectral feature is interpreted by the heating effect of manganese spins. Polarization dependence of the spin heating is observed for the first time, revealing the contribution of spin flip between excitons and magnetic ions to the heating process.

在自旋跨界材料（例如自旋跨界复合物和半磁性半导体）中研究了低自旋状态之间的光载过程。（1）通过测量吸收光谱和磁敏感性，研究了光诱导的磁相变的旋转型磁相变种的旋转交叉复合物中的光诱导的磁相变种的磁相转变。在低旋转状态和高旋转状态之间的照片旋转过程中，已经观察到非线性特征，例如阈值行为，孵化周期和相位分离。这些结果表明，由自旋晶格相互作用介导的合作跨系统穿越在驱动新类别非平衡现象的过程中起关键作用。此外，事实证明，这种光诱导的磁相过渡过程受到外部磁场的极大影响。（2）在半磁性半磁性半磁性半磁性的半磁性半磁性半磁性半磁性半导体CD _ 0.9> mn_ <0.9> mn_ <0.0.1> vriencon中，光诱导的磁相变量在半磁性半导体分解的磁性磁光发光实验中进行。观察到Zeeman移位的还原和磁极的结合能。光谱特征是通过锰旋转的加热效应来解释的。首次观察到自旋加热的极化依赖性，揭示了激子和磁离子之间自旋翻转对加热过程的贡献。