Study of novel piezoelectric responses in highly conductive materials

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02424
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 26020:Inorganic materials and properties-related
• Research Institution: The University of Tokyo
• Principal Investigator: SHIOMI YUKI 東京大学, 大学院総合文化研究科, 准教授 (10633969)
• Co-Investigator(Kenkyū-buntansha): 石渡 晋太郎 大阪大学, 基礎工学研究科, 教授 (00525355)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 圧電効果 / 磁性金属 / 磁気圧電効果 / ネマティック秩序 / 奇パリティ多極子

Outline of Final Research Achievements

Experimental research was performed with the aim of developing conductive piezoelectric materials. We newly constructed a measurement system of the inverse piezoelectric effect under low temperature and magnetic field using a laser Doppler vibrometer. We systematically studied temperature dependence of piezoelectric responses for various conductive materials. Notably, we discovered a new piezoelectric effect called the magnetopiezoelectric effect in magnetic metals with broken time-reversal and space-inversion symmetries. By examining the temperature dependence of the magnetopiezoelectric effect, we found that the magnetopiezoelectric signal increases with decreasing temperature, and the its efficiency reaches the same level as typical piezoelectric materials at the lowest temperature.

Free Research Field

物性物理学

Academic Significance and Societal Importance of the Research Achievements

これまで伝導性を有する物質材料は、伝導電子によるスクリーニング効果によって圧電応答が妨げられるために、有効な圧電材料にはならないと考えられてきた。しかしながら研究代表者は超イオン伝導性や磁性の自由度を有効に用いることでこの常識を打ち破り、新たに伝導を有する物質の圧電材料としての有用性を見出した。特に、磁気圧電効果と呼ばれる低対称金属における新しい圧電現象の発見を達成した。