|Speakers: Dr. Sandeep Kumar
UNIST (Ulsan National Institute of Science and Technology), Korea
X-ray Free Electron Laser facilities currently provide the brightest X-ray pulses available, typically with millijoule (mJ) energy and several hundred-femtosecond duration. There is, however, a great demand for even higher power and shortest pulse duration at high photon energy. We demonstrate a 100 attosecond-Terawatt (as-TW) X-ray pulse in X-ray free-electron laser controlled by a few cycle IR pulse. Single current spike in an electron bunch is utilized repeatedly to amplify a seeded radiation to a terawatt level. This scheme is relatively simple, compact, straightforward, and produces a temporally and spectrally clean pulse. The generated attosecond X-ray pulse is synchronized to the driving few cycle pulse, hence, well suited to the pump-probe experiments in the study of ultrafast dynamics. The viability of this scheme is demonstrated in simulations using Pohang accelerator laboratory (PAL)-XFEL beam parameters. To further shortening the XFEL pulses, electron-beam energy chirp effect, mode locking in XFEL and Raman compression for XFEL pulses will be explored.