In the world of scientific research, a new unit of time has captured the attention of scientists – the attosecond, which is a billionth of a billionth of a second. With modern technologies, it is now possible to create ultra-short x-ray impulses measured in attoseconds, allowing scientists to observe subatomic particles in their natural environment.
Earlier this year, researchers made headlines by using this method to visualize the movement of electrons in liquid water. This breakthrough has great potential for advancing fields such as chemistry and biology, as scientists will be able to observe electron movements in various molecules.
The primary tool for such research is the free-electron laser (XFEL), such as the Linac Coherent Light Source (LCLS) in California. This laser generates intense x-rays, causing electrons to move randomly, which can then be visualized when formed into short pulses.
Scientists use the “pump-probe” method to observe electrons using XFEL. By exciting the target with one pulse and then probing it with another, researchers can observe subatomic particles in their quantum state before any potential damage occurs due to the x-rays.
In a recent study published by experimenters from LCLS, the pulse duration was reduced to a record 270 attoseconds. This achievement is a significant step forward in the “pump-probe” method and demonstrates the capabilities of the researchers in understanding electron movements within molecular systems.
James Cryan, a senior researcher at SLAC, emphasized the importance of attosecond research in understanding electron movements and interactions within molecules. While LCLS is not the only XFEL in the world conducting experiments with attosecond pulses, it boasts the highest capabilities in its class. Researchers at LCLS have successfully used the “pump-probe” method with attosecond times to visualize electron movements in liquid water.