High-pressure neutron diffraction study of heavy-electron antiferromagnetic states

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K03737
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 13030:Magnetism, superconductivity and strongly correlated systems-related
• Research Institution: Tohoku University
• Principal Investigator: Ikeda Yoichi 東北大学, 金属材料研究所, 助教 (40581773)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 中性子回折 / 高圧力

Outline of Final Research Achievements

The aim of the project is to develop a high-pressure apparatus for neutron diffraction experiments, which is available to keep a high-pressure condition of 4-5 GPa, and to get an additional insight into magnetic phases of CeNiGe3 under high pressure. We have succeeded in observing magnetic Bragg reflections with our high-pressure apparatus under high pressure, though the applied pressure is lower than the target pressure (4-5 GPa). In addition, we found that the incommensurate magnetic propagation wave vector of the low-pressure antiferromagnetic phase possibly shifts to a commensurate point, indicating a possible incommensurate-to-commensurate magnetic transition under high pressure. Further upgrade of our high-pressure apparatus is under consideration.

Free Research Field

固体物理

Academic Significance and Societal Importance of the Research Achievements

圧力は温度と並んで，物質の状態を変えるひとつのパラメータであるものの，物質中の電子状態を変えるためには数万気圧程度の圧力が必要となります。先人による様々な努力の結果，近年では多くの実験が比較的手軽に実施できるようになりましたが，物質の微視状態を調べる中性子やＸ線による実験のためには更なる工夫が必要です。我々は物質の磁気状態を調べるために，数万気圧の圧力下で比較的大きな試料（1mm3）でも実験のできる圧力セルを開発し，圧力下の磁気状態の変化を捉えることに成功しました。目標とした圧力には届いていないため更なる改良は必要ですが，今後，物質の新しい状態を捉えることが出来る可能性があります。