The Institute of Scientific and Industrial Research, Osaka University


LAST UPDATE 2017/02/26

  • 研究者氏名
    Researcher Name

    楊金峰 Jinfeng YANG
    准教授 Associate Professor
  • 所属
    Professional Affiliation

    The Institute of Scientific and Industrial Research, Osaka University

    Nanoscience and Nanotechnology Center
  • 研究キーワード
    Research Keywords

    Accelerator & beam science
    Pulse radiolysis
    Time-resolved electron microscopy
    Ultrafast phenomena and dynamics
Research Subject
Development of femtosecond time-resolved electron microscopy

研究の背景 Background


More recently, ultrafast phenomena in materials such as phase transitions, charge/energy transformations and chemical reactions are a significant and growing interest in designing new materials and devices for application. To understand such ultrafast phenomena, the motion of atoms or molecules in the physics-chemical processes in matter is necessary to be observed directly. A measurement technique with femtosecond temporal resolution and sub-nanometer spatial resolution has long been a goal for the scientists.

研究の目標 Outcome


The main objective of the research is to develop a time-resolved electron microscopy with 100 fs temporal resolution and 1 nm spatial resolution (which called ultrafast electron microscopy, UEM) using a relativistic-energy and femtosecond-pulse electron source. The electron source, which is called RF gun, is driven by a femtosecond laser and a radio-frequency (2856 MHz, RF) accelerator. The UEM will be used to observe the fundamental dynamic processes in matter occurring on femtosecond time scales over atomic spatial dimensions.

研究図Research Figure

Fig.1. Femtosecond time-resolved electron microscopy and its applications Fig.2. Femtosecond-pulse electron source (RF gun) RF source Photocathode Cu, Mg Femtosecond laser 2856MHz、~MW fs, λ=266nm RF accelerating cavities electric field: ~100MV/m Femtosecond e- bunch with MeV energy Space-charge effect is reduced! 15cm Fig.3. Electron bunch length and energy spread as a function of beam energy generated from the RF gun

文献 / Publications

<詳解>フェムト秒時間分解電子顕微鏡の研究、電気学会論文誌 IEEJ Trans. on Electronics, Information and Systems, Vol. 134, No. 4 pp.515-520, 2014. Appl. Phys. Lett. 103, 253107(2013); 98, 251903(2011). Phys. Rev. B 88, 184101(2013). Nucl. Instru. Methods A 637, S24(2011). Radiat. Phys. Chem. 78, 1106(2009)