Quantum Radiation Energy
Advanced Energy Generation Division Quantum Radiation Energy Research Section
Professor : Hideaki OHGAKI
Associate Professor : Toshiteru KII
Assistant Professor : Heishun ZEN
Research on Generation and Application of New Quantum Radiations, i.e. Compact MIR Free Electron Laser, Table-Top THz coherent radiation, and Laser-Compton Gamma-ray. International collaboration research on renewable energy implementation in ASEAN has
also been promoted.
Generation and Application of New Quantum Radiation
Generation and application of new quantum radiations from relativistic electron beams have been studied. Free electron laser, which is generated by a high brightness electron beam from accelerator, is considered as one of new generation radiation sources. FEL is tunable laser with a high power. We have developed a thermionic cathode RF gun with our original RF control system to generate mid-infrared FEL with compact accelerator system. In 2008 we succeeded in FEL power saturation at 13.6μm in wavelength and now the FEL can provide the intense laser light in the wavelength region from 3.4 to 26μm.
As application researches, we promote the mode-selective phonon excitation experiment to study on wide-gap semiconductors in cooperation with in-house users as well as outside users. Generation and application of Laser-Compton Gamma-ray beam has been studied for the nuclear safeguard and nuclear security. A short period undulator consists of bulk high Tc superconducting
magnet and table- top THz coherent radiation have been studied as well.
Principle of FEL
Generation of Free Electron Laser (FEL) is based on the microbunching phenomenon driven by a high brightness electron beam which interacts with electro-magnetic field.
Wavelength Tunability of KU-FEL.
This graph shows the wavelength tunability of KU-FEL. We can freely change the FEL wavelength from 3.4 to 26 μm by changing the electron beam energy from 36 to 20 MeV and magnetic field strength of the undulator. The spectral width of the FEL is around 1-3 percent in FWHM.
Conceptual drawing of the assay system for hidden material by using Laser-Compton backscattering gamma-rays.
Quasi-monochromatic gamma-ray beam generated by collision between a high energy electron beam and a high power laser can be used for detection of hidden dangerous material.