Development of Broadband mid-IR sources via FDML

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20500
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0402:Nano/micro science, applied condensed matter physics, applied physics and engineering, and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: Nakamura Tauma 東京大学, 大学院理学系研究科(理学部), 特任助教 (40906252)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: Mid IR laser / Intra-pulse DFG / Raman spectroscopy

Outline of Final Research Achievements

We developed the robust 12fs, 3.3W, 50MHz mode-locked laser based on Yb:fiber laser system. Using this laser, Broadband intra-pulse DFG with more than 1 mW output has been developed, which is the first demonstration of Broadband intra-pulse DFG via 1um fiber lasers.
With this ultrashort pulse laser, we also developed broadband Raman Spectroscopy system. By utilizing Time-stretch method, we achieved a record acquisition rate of 50 Mspectra/s was achieved, which corresponds to 500 times faster than previous state-of-the-art. This spectroscopy gives the fastest temporal resolution, which has a great potential to reveal unknown ultrafast molecular dynamics.

Free Research Field

Spectroscopy

Academic Significance and Societal Importance of the Research Achievements

分子の指紋領域を一括で取得する事が可能である広帯域な中赤外光源は非常に高い需要があるが、今日の最先端のレーザー技術をもってしても、十分なスペクトル幅や、輝度、高い繰り返し周波数、システムの安定性のすべてを兼ね備える事は非常に困難である。高輝度化で有利な1umで広帯域中赤外光を実現できた意義は大きい。
また、開発したラマン分光システムは、分子指紋領域における従来のいかなる手法と比較しても世界最速の分光を実現できた。このことは今までアクセスが出来なかったsub-usの分子のダイナミクス解明に大きな寄与をもたらすと考えられる。