Rare event processes at surfaces driven by THz pulses

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H00343
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 29:Applied condensed matter physics and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Yoshinobu Jun 東京大学, 物性研究所, 教授 (50202403)
• Co-Investigator(Kenkyū-buntansha): 松永 隆佑 東京大学, 物性研究所, 准教授 (50615309)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 表面 / 反応 / 振動分光 / テラヘルツ / 超短パルスレーザー / 和周波発生 / 光物性

Outline of Final Research Achievements

In this study, we have constructed the wavelength-tunable narrow-band terahertz pulse generation system by difference frequency generation from a twin-type optical parametric amplifier with a regenerative amplifier. We have also constructed an intense ultra-broadband terahertz pulse system covering from sub-terahertz to mid-infrared region by using two-color laser-induced air plasma. Time-resolved wide-range vibrational sum frequency generation spectroscopy can be measured at once by using the ultra-broadband THz system. Time-resolved THz spectroscopy has been carried out to study the photo-excited carrier dynamics of Dirac electrons in solid states. The reaction dynamics of adsorbed molecules on model catalyst surfaces using THz pulses was also studied.

Free Research Field

表面科学

Academic Significance and Societal Importance of the Research Achievements

狭帯域および超広帯域のテラヘルツパルスを発生するシステムを構築し、テラヘルツパルスによる時間分解分光や振動共鳴和周波発生分光の開発を行った。これらの分光法は、固体表面科学だけでなく、固体光物性、電気化学、触媒化学、界面科学、電子デバイス、ソフトマテリアルなど様々な対象に適用でき、応用範囲が広い。しかも、超高速現象を時間分解で観測することが可能なので、それぞれの分野で未知であったダイナミクスの解明につながると期待される。