Study on spin structures and electron-lattice interaction of nanomaterials using nuclear resonant scattering.

利用核共振散射研究纳米材料的自旋结构和电子晶格相互作用。

基本信息

批准号：
15540308
负责人：
SETO Makoto
金额：
$ 2.11万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

Nanostructured materials like quantum wires have attracted much interest for their novel properties and the possibilities for new devices. It is well known that nanostructured materials show different electric and thermodynamical properties as compared to ordinary macroscopic materials. For the further understanding and new applications, microscopic studies on nanosized materials are indispensable.We have measured the time and energy spectra of nuclear resonant scattering of synchrotron radiation from magnetic Fe nanowires to investigate the electronic states and lattice dynamics of the Fe nanowires, As for the electronic states, we studied the correlation between the spin structure and the shape of the wires. From the measured time spectra of the Fe nanowires, the value of internal magnetic field is obtained to be 32.9 T. This agrees with the value of the bulk Fe (33 T), and this result indicates the electronic state of Fe atoms in our nanowire sample is almost the same as that of Fe atoms in a bulk sample. Furthermore, it was confirmed that the direction of the magnetic field is anisotropic and coincides with the direction of the nanowires. Our results show that this method is useful for the study of electronic states of nanomaterilas. As for the vibrational states, we studied the difference between the bulk state and the nanowires. Because it is possible to obtain the information on the specific elements by using nuclear resonant scattering, we can obtain the intrinsic lattice dynamics of nanoweires without the vibration of the substrate material. The observed phonon spectra show the dependence on the size of the samples, and we concluded it is due to the anharmonic effect.

纳米结构的材料（例如量子线）对其新型特性和新设备的可能性引起了极大的兴趣。众所周知，与普通的宏观材料相比，纳米结构材料显示出不同的电力和热力学特性。为了进一步的理解和新的应用，对纳米材料的微观研究是必不可少的。我们已经测量了从磁性Fe纳米线的同步辐射的核共振散射的时间和能量光谱，以研究电子状态的电子状态和Fe纳米状态的电子状态和晶状体动力学，因为我们研究了电子状态，而我们研究的是在旋转结构之间的旋转结构和形状的旋转线和形状。从Fe纳米线的测得的时间光谱中，获得内部磁场的值为32.9 t。这与大量Fe（33 t）的值一致，并且该结果表明我们的纳米线样品中Fe原子的电子状态与Bulk样品中的Fe原子几乎相同。此外，已经证实磁场的方向是各向异性的，并且与纳米线的方向一致。我们的结果表明，该方法对于研究纳米物质的电子状态很有用。至于振动状态，我们研究了散装状态和纳米线之间的差异。因为可以使用核共振散射获得有关特定元素的信息，所以我们可以在没有底物材料振动的情况下获得纳米线的固有晶格动力学。观察到的声子光谱显示出对样品大小的依赖性，我们得出的结论是由于非谐作用。