#2023 W 42 D 2 GMT +08:00. Indicate #75 days to go in 2023. In 2005, the University of Ottawa wondered how fast it was a classical electron made one Bohr orbit in 150 attoseconds. However, the trouble was that to meet the goals of attosecond physics, advances in a single neat extreme ultraviolet pulse streak camera determined that single pulses had been localized to a time scale. Then, this idea was implemented in 2012 by Prof. Huilier and teams by doing an experiment with special emphasis laid on a time-delay experiment, where the attosecond phase of XUV pulses is used to photo-ionize target atoms at well-defined times, which probing process in real-time by a phase-locked. Finally, in 2018, researchers at the National Accelerator Laboratory developed a way to produce X-ray laser bursts that are several hundred attoseconds long. The result of this method is addressed as X-Ray Laser Enhanced Attosecond Pulse (XLEAP). However, how do you think this is being applied? Will this become the future free electron laser?