Photoinduced phase transition mechanism in strongly correlated transition metal oxide system revealed by time-resolved x-ray diffraction

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14347
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Fukaya Ryo 大学共同利用機関法人高エネルギー加速器研究機構, 物質構造科学研究所, 特任助教 (30735072)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 光誘起相転移 / 強相関電子系 / 時間分解X線回折 / 超高速光科学 / コバルト酸化物 / 光物性 / 物性実験 / 磁性

Outline of Final Research Achievements

Photoinduced phase transition dynamics with transient change of lattice and electronic-ordered state in strongly correlated transition metal oxide system has been observed by time-resolved x-ray diffraction using picosecond synchrotron x-ray pulse and femtosecond x-ray free electron laser pulse. The experimental results have revealed that the cooperative interaction between lattice and electronic order in femtosecond-to-picosecond region play an important role to lead the macroscopic electronic and structural phase transitions in nanosecond region.

Free Research Field

光誘起相転移

Academic Significance and Societal Importance of the Research Achievements

本研究で実施した時間分解X線回折法は、従来の非平衡物質科学分野で不足していた構造や電子秩序状態変化の直接的な情報を、フェムト秒―ナノ秒領域にわたり実時間計測を可能にする極めてユニークな手法であり、先端的なX線パルス光源を利用して実施した本研究の学術的意義は極めて大きい。本研究を通して明らかとなった、強相関電子系が織りなす電子の内部自由度と格子との相関が、応用に向けた制御方法や新奇な光機能性を有する物質の探索及び創成に明確な指針を与えることになると期待される。