Anomalous spin fluctuations new the Molt transition in manganites

异常自旋波动新的锰酸盐蜕皮转变

• 批准号: 10640329
• 负责人: YOSHIZAWA Hideki
• 金额: $ 1.92万
• 依托单位: The University of Tokyo, Institute for Solid State Physics
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640329/
• 关键词: Neutron diffraction; Colossal magnefoesistance; Charge ordering; 巨大磁気抵抗; Mn酸化物; 中性子散乱; スピンダイナミクス

The hole concentration dependence of the crystal and magnetic structures of the hole doped manganite systems have been studied systematically with use of neutron diffraction technique, and their phase diagrams have been determined. The studies on the spin dynamics further revealed that the spin fluctuation changes its nature from ferromagnetic correlations to antiferromagnetic correlations at and near the charge ordering transition temperature. We discovered that the spin ordering in the CE-type charge/spin ordered state is not a true long range order. The orbital degree of freedom gives rise to two domains of orbital ordering patterns, and reduces the spin correlation, in the CE-type order.

本文用中子衍射技术系统地研究了空穴掺杂锰氧化物体系的晶体结构和磁结构与空穴浓度的关系，并测定了它们的相图。自旋动力学的研究进一步揭示了在电荷有序转变温度及附近，自旋涨落的性质从铁磁关联转变为反铁磁关联。我们发现CE型电荷/自旋有序态中的自旋有序不是真正的长程有序。轨道的自由度产生两个域的轨道排序模式，并减少自旋相关，在CE型顺序。

项目成果

R. Kajimoto, T. Kakeshita, Y. Oohara, H. Yoshizawa. Y. Tomioka, and Y. Tokura: "Anomalous ferromagnetic spin fluctuations in an antiferromagnetic insulator PrィイD21-xィエD2CaィイD2xィエD2MnOィイD23ィエD2"Phys. Rev. B. 58. R11837-R11840 (1998)

R. Kajimoto、T. Kakeshita、Y. Oohara、H. Yoshizawa、Y. Tomioka 和 Y. Tokura：“反铁磁绝缘体 D21-x、D2Ca、D2x、D2MnO Phys. Rev. B. 58 中的异常铁磁自旋涨落.R11837-R11840 (1998)

T. Katsufuji, T. Tanabe, Y. Tokura, T. Kakeshita, R. Kajimoto, and H. Yoshizawa: "Commensurability effect on the charge ordering of LaィイD22-xィエD2SrィイD2xィエD2NiOィイD24ィエD2"Phys. Rev. B. 60. R5097-R5100 (1999)

T. Katsufuji、T. Tanabe、Y. Tokura、T. Kakeshita、R. Kajimoto 和 H. Yoshizawa：“D22-x D2Sr D2x D2NiO D24D2 电荷排序的可通约性效应”Phys. Rev. B. 60. R5097 -R5100 (1999)

R. Kajimoto: "Anomalous ferromagnetic spin fluctuations in an antiferromagnetic insulator Pr_<1-x>Ca_xMnO_3"Phys. Rev. B. 58. R11837-11840 (1998)

R. Kajimoto：“反铁磁绝缘体 Pr_<1-x>Ca_xMnO_3 中的异常铁磁自旋波动”Phys。

M.Kubota: "Impact of La substitution on the magnetic structure of a low-carrier-densitry kondo system: Ce_<ag> La_<ar>P"Phys.Rev.B. 58. R2929-2932 (1998)

M.Kubota：“La 取代对低载流子密度 kondo 系统磁结构的影响：Ce_<ag> La_<ar>P”Phys.Rev.B。

K.Hirota: "Neutron-diffraction studies on the magnetic ordering process in the layest Mn perovskite La_<2-2x> Sr_<1+2x> Mn_2 O_7"J.Phys.Soc.Jpn.. 67. 3380-3383 (1998)

K.Hirota：“层状 Mn 钙钛矿 La_<2-2x> Sr_<1 2x> Mn_2 O_7 磁有序过程的中子衍射研究”J.Phys.Soc.Jpn.. 67. 3380-3383 (1998)