Study of anomalous photo-excited states near phase transitions in strongly correlated electron systems

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05122
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics I
• Research Institution: Chiba University
• Principal Investigator: Mino Hirofumi 千葉大学, 国際教養学部, 准教授 (40323430)
• Co-Investigator(Renkei-kenkyūsha): SAKAI Masatoshi 千葉大学, 工学研究院, 准教授 (60332219) ; KATO Tetsuya 千葉大学, 教育学部, 教授 (00224519)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 光励起状態 / スペクトル計測 / 磁気分光 / 強相関電子系

Outline of Final Research Achievements

To observe the changes in electronic states induced by photo-excitation, we have developed a multichannel differential integration spectroscopy system. With photo-excitation intensity and polarization modulation, the measurements in the wavelength range from 300 nm to 900 nm were realized under magnetic field up to 7 T and at a temperature between 1.5 K to room temperature. The Zeeman splittings of the heavy-hole and light-hole exciton transitions in magnetic semiconductor quantum wells and higher order exciton transition with fine spectrum structure in lead halide perovskite single crystals were clearly observed. Furthermore, in the organic Mott insulator β '(BEDT - TTF) (TCNQ) crystal, the reflection spectrum change in the wide wavelength region caused by photo-excited states, which show spatial expansion, was obtained near the antiferromagnetic transition temperature.

Free Research Field

半導体光物性