Chen Xiang-Bai, Hien Nguyen Thi Minh, Han Kiok, Nam Ji-Yeon, Huyen Nguyen Thi, Shin Seong-Il, Wang Xueyun, Cheong S W, Lee D, Noh T W, Sung N H, Cho B K, Yang In-Sang
School of Science and Laboratory of Optical Information Technology, Wuhan Institute of Technology, Wuhan 430205, China.
Department of Nano Science &Mechanical Engineering and Nanotechnology Research Center, Konkuk University, Chungju 380-701, Korea.
Sci Rep. 2015 Aug 24;5:13366. doi: 10.1038/srep13366.
Spin-wave (magnon) scattering, when clearly observed by Raman spectroscopy, can be simple and powerful for studying magnetic phase transitions. In this paper, we present how to observe magnon scattering clearly by Raman spectroscopy, then apply the Raman method to study spin-ordering and spin-reorientation transitions of hexagonal manganite single crystal and thin films and compare directly with the results of magnetization measurements. Our results show that by choosing strong resonance condition and appropriate polarization configuration, magnon scattering can be clearly observed, and the temperature dependence of magnon scattering can be simple and powerful quantity for investigating spin-ordering as well as spin-reorientation transitions. Especially, the Raman method would be very helpful for investigating the weak spin-reorientation transitions by selectively probing the magnons in the Mn(3+) sublattices, while leaving out the strong effects of paramagnetic moments of the rare earth ions.
当通过拉曼光谱清晰观察到自旋波（磁振子）散射时，它对于研究磁相变而言可以既简单又有效。在本文中，我们展示了如何通过拉曼光谱清晰观察磁振子散射，然后将拉曼方法应用于研究六方锰氧化物单晶和薄膜的自旋排序及自旋重取向转变，并直接与磁化测量结果进行比较。我们的结果表明，通过选择强共振条件和合适的偏振配置，可以清晰观察到磁振子散射，并且磁振子散射的温度依赖性对于研究自旋排序以及自旋重取向转变而言可以是一种简单而有效的量度。特别地，拉曼方法对于通过选择性探测Mn(3+)亚晶格中的磁振子来研究微弱的自旋重取向转变非常有帮助，同时可以排除稀土离子顺磁矩的强烈影响。
