Direct Observation of Orbital Ordering in Light Transition Metal Oxides by Soft-X Ray Core Absorption Spectroscopy with Linearly Polarized Light

利用线性偏振光软 X 射线核心吸收光谱直接观察轻质过渡金属氧化物的轨道有序性

基本信息

批准号：
13440113
负责人：
KIMURA Akio
金额：
$ 7.87万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

We have developed the experimental system to observe a linear dichroism in core absorption spectra using soft X-ray synchrotron radiation at Hiroshima Synchrotron Radiation Center (HSRC) of Hiroshima University. Using this system, we study orbital ordering, which possibly exists in several 3d transition metal oxides involving Ti and V atoms. These transition metal oxides are fabricated in our group. Our research goal is to find if the orbital ordering exists in these transition metal oxides and also to relate the spin ordering with the orbital ordering.During the first fiscal year (H13), we have developed the observation system, which was attached to the beam-line of HiSOR, the strage ring at HSRC. We also attached the cryostat with the heater to the sample manipulator, which enabled us to change the sample temperature from 10K to 300K. In the first fiscal year, we newly bought a low energy electron diffraction (LEED) system for the check of the sample surface cleanliness. We finished the adjustment of the beamline at HiSOR by the end of the year (H13). As a result, we could use the light beam in the photon energy range of 400-1000eV with the photn flux of 10^8-10^9 photons/sec. At the second fiscal year, we actually performed the experiment on single crystalline VTiO3, which has been fabricated in our research group. We could observe the difference between the absorption coefficients with the light polarization vector parallel to a and b axes. We are now analyzing data and going to clarify the relationship between the orbital ordering and the physical properties.

我们已经开发了实验系统，以使用广岛大学的广岛同步加速器辐射中心（HSRC）的软X射线同步辐射观察核心吸收光谱中的线性二色性。使用该系统，我们研究了轨道顺序，它们可能存在于涉及Ti和V原子的几种3D过渡金属氧化物中。这些过渡金属氧化物是在我们组中制造的。我们的研究目标是找到这些过渡金属氧化物中的轨道订购是否存在，并将旋转顺序与轨道订购联系起来。在第一个财政年度（H13），我们已经开发了观测系统，该观察系统已附加到光束上 - Hisor的行，HSRC的Strage Ring。我们还将低温恒温器与加热器连接到样品操纵器，这使我们能够将样品温度从10K更改为300K。在第一个会计年度，我们新购买了一个低能电子衍射（LEED）系统，以检查样品表面清洁度。我们在今年年底之前完成了光束线的调整（H13）。结果，我们可以将光束在400-1000EV的光子能量范围内使用，而光束的光束为10^8-10^9光子/秒。在第二会计年度，我们实际上在研究小组中制造的单晶VTIO3上进行了实验。我们可以观察到具有平行于A和B轴的光偏振矢量的吸收系数之间的差异。现在，我们正在分析数据，并阐明轨道订购与物理属性之间的关系。