Light induced ferroelectricity by cooperative Jahn-Teller effect

2017 Fiscal Year Final Research Report

• Project/Area Number: 26620055
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Functional solid state chemistry
• Research Institution: Tohoku University
• Principal Investigator: Shojiro Kimura 東北大学, 金属材料研究所, 准教授 (20379316)
• Co-Investigator(Kenkyū-buntansha): 中野 元裕 大阪大学, 理学研究科, 教授 (00212093)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 光誘起相転移

Outline of Final Research Achievements

In this research, we aim to find light induced ferroelectricity in the spin crossover complex [MnIII(taa)]. [MnIII(taa)] molecule possesses a electric dipole moment due to a dynamic Jahn-Teller effect in its high spin state. Because of an existence of a cooperative interaction between electric dipole moments, the ferroelectricity is expected to appear by light induced spin crossover from the low spin to the high spin state. To find this phenomenon, the dielectric and electric polarization measurement systems, and microwave ESR system, in which the measurements under illumination of light can be carried out, were developed. Although the light induced ferroelectricity was not observed, we found interesting magnetocapacitance effects, in which the dielectric constant changes more than 100% by applied magnetic field.

Free Research Field

磁性物理学