Research on the ground state of electrons of an orbital-ordering perovskite Ti oxide by the X-ray magnetic diffraction experiment

X射线磁衍射实验研究轨道有序钙钛矿钛氧化物电子基态

• 批准号: 16340098
• 负责人: ITO Masahisa
• 金额: $ 10.11万
• 依托单位: Gunma University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16340098/
• 关键词: X-rav Magnetic Diffraction; X-rav Magnetic Scatterine; Soin Magnetic Form Factor; Orhital Maggnetic Form Fartor; Spin Density; Orbital Ordering; Perovskite Titanium Oxide; ペロブスカイト酸化物; 強磁性体; YTiO_3

Perovskite oxide YTiO_3 has peculiar solid-state properties; it shows orbital ordering and becomes ferromagnetic below 30K. Origin of the both properties is 3d electrons of Ti atoms. The aim of this research is to elucidate the peculiar properties of the perovskite titanium oxide YTiO_3 by using synchrotron radiation X-rays. We utilize two kinds of experimental methods, l) the X-ray magnetic diffraction (XMD) and 2) the magnetic Compton scattering (MCP), which are elastic and inelastic scattering of elliptically polarized synchrotron radiation X-rays by magnetic moments. Wavefunctions of magnetic electrons are observed in the reciprocal lattice space(or its Fourier transformed real space) by the former method, and in the momentum space by the latter method. Concrete purpose of this study is to clarify the ground state of the 3d electrons of Ti atoms in YTiO_3 through direct observation of the electrons orbital by synchrotron radiation.We have upgraded the XMD experimental system in ord … More er to produce magnetic field of over 2T that is needed for saturating the magnetization even along the hard magnetization direction of this compound, as both experimental methods of XMD and MCP require the magnetization of the specimen to be saturated. By this upgrade of the experimental system we ca perform the XMD experiment under the condition in which the magnetization of the specimen crystal is saturated along any crystallographic direction.We have obtained the following results from the XMD experiment.(1) We could measure spin magnetic form factor for all principal crystallographic axes of YTiO_3.(2) We have succeeded in obtaining three dimensional distribution of spin density of YTiO_3 in the real space for the first time.(3) The obtained spin density distribution was represented very well by the electron distribution of 3d-electons in the t2g state. This would be the first direct observation of a specific 3d electron orbital in the three dimensional real space. In the MCS experiment we could measure the magnetic Compton profile (MCP) of an orbital-ordering ferromagnetic compound for the first time. By comparing the observed MCP with the calculated MCP based on a model wavefunction we could determine the ground-state wavefunction of the 3d electron. In conclusion we could elucidate the ordered orbital (ground state wavefunction) of the 3d electrons of YTiO_3 in the real space and momentum space. Less

过氧化氢氧化物YTiO_3具有特殊的固态性质，在30K以下表现出轨道有序性并成为铁磁性。这两种性质的根源是Ti原子的3d电子。本研究的目的是利用同步辐射X射线阐明钙钛矿型氧化钛YTiO_3的特殊性质。我们采用了两种实验方法：1）X射线磁衍射（XMD）和2）磁康普顿散射（MCP），它们是磁矩对椭圆偏振同步辐射X射线的弹性和非弹性散射。前一种方法在倒易晶格空间（或其傅立叶变换后的真实的空间）中观测到磁电子的波函数，后一种方法在动量空间中观测到磁电子的波函数。本研究的具体目的是利用同步辐射直接观测YTiO_3中Ti原子的3d电子轨道，以确定其基态。 ...更多信息 因此，产生超过2T的磁场，这是饱和磁化所需的，甚至沿着该化合物的硬磁化方向，因为XMD和MCP的实验方法都需要样品的磁化饱和。通过对实验系统的改进，我们可以在样品晶体的磁化强度沿沿着任意晶向饱和的条件下进行XMD实验。(1)我们可以测量YTiO_3所有主晶轴的自旋磁形状因子。(2)我们首次成功地获得了YTiO 3在真实的空间中自旋密度的三维分布。(3)所获得的自旋密度分布由t2g态中的3d电子的电子分布很好地表示。这将是在三维真实的空间中第一次直接观测到特定的三维电子轨道。在MCS实验中，我们可以测量磁康普顿轮廓（MCP）的轨道有序铁磁化合物的第一次。通过比较观测到的MCP和基于模型波函数计算得到的MCP，确定了3d电子的基态波函数，从而阐明了YTiO_3的3d电子在真实的空间和动量空间中的有序轨道（基态波函数）。少

项目成果

Observation of 3D Spin Density Distribution of Ferromagnetic YTiO_3 by X-Ray Magnetic Diffraction

X射线磁衍射观察铁磁性YTiO_3的3D自旋密度分布

• 发表时间: 2007
• 期刊: Photon Factory Activity Report 24・B
• 作者: M.Itoh;I.Yamauchi;T.Kozuka;T.Suzuki;T.Yamauchi;J.Yamaura;Y.Ueda;Kosuke Suzuki
• 通讯作者: Kosuke Suzuki

Spin density and ordered orbital of YTiO_3 observed by X-ray magnetic diffraction

X射线磁衍射观察YTiO_3的自旋密度和有序轨道

• 发表时间: 2005
• 期刊: Acta Crystallographica A Vol.61
• 作者: Naruki Tsuji;Masahisa Ito;Hiromitsu Akiyama;Kousuke Suzuki;Hiromichi Adachi;Hironori Nakao;Youichi Murakami;Yasujiro Taguchi;Yoshinori Tokura
• 通讯作者: Yoshinori Tokura

放射光X線磁気分光と散乱

同步加速器X射线磁谱和散射

• 发表时间: 2007
• 作者: M.Ito;N.Tsuji;F.Itoh;H.Adachi;E.Arakawa;K.Namikawa;H.Nakao;Y.Murakami;Y.Taguchi;Y.Tokura;G.-Q.Zheng;橋爪 弘雄
• 通讯作者: 橋爪 弘雄

Magnetic Compton profile study of orbital ordering state of 3d electrons in YTiO_3

YTiO_3中三维电子轨道有序态的磁康普顿剖面研究

• 发表时间: 2009
• 期刊: J. Phys. Soc. Jpn 77
• 作者: Kasaya;T.;T. Goto;K. Baba;M. Kinoshita;Y. Hamano;and Y. Fukao;N. Tsuji
• 通讯作者: N. Tsuji

X線磁気回折実験システムの高度化と軌道整列ペロブスカイト酸化物の磁性研究への応用

X射线磁衍射实验系统的进展及其在轨道排列钙钛矿氧化物磁学研究中的应用

• 发表时间: 2006
• 期刊: 群馬大学サテライト・ベンチャー・ビジネス・ラボラトリー平成17年度年報
• 作者: T.Shiraoka;T.Kiyama;M.Itoh;L.Kano;H.Ichikawa;J.Akimitsu;鈴木 宏輔
• 通讯作者: 鈴木 宏輔