February 18, 2013
In The Blink Of An Eye: X-Ray Imaging On The Attosecond Timescale
Berkeley Lab research at AAAS Meeting
In the blink of an eye, more attoseconds have expired than the age of Earth measured in — minutes. A lot more. To be precise, an attosecond is one billionth of a billionth of a second. The attosecond timescale is where you must go to study the electron action that is the starting point of all of chemistry. Not surprisingly, chemists are most eager to explore it with X-rays, the region of the electromagnetic spectrum that can probe the core electrons of atoms, the electrons that uniquely identify atomic species.Heralded as the science of the 21st century by Science and The Economist, attosecond science is a new frontier of molecular and material science. It is expected to catalyze novel applications in a wide range of fields such as nanotechnology and life sciences, based on the ultimate visualization and control of the quantum nature of the electron.
Ali Belkacem, a chemist with the Lawrence Berkeley National Laboratory, has been using powerful laboratory-scale lasers to test whether multidimensional nonlinear x-ray spectroscopy on the attosecond timescale is practical for the light sources of the future — and just what combination of beam characteristics is needed to define them.
"Chemistry is inherently dynamical," he has said. "That means, to make inroads in understanding — and ultimately controlling — chemical reactions we have to understand how atoms combine to form molecules; how electrons and nuclei couple; how molecules interact, react, and transform; how electrical charges flow; and how different forms of energy move within a molecule or across molecular boundaries. Most importantly, we have to know how all these things behave in a correlated way, dynamically in time and space, both at the electron and atomic levels."
Belkacem will give a presentation at the 2013 AAAS annual meeting in Boston titled "Attosecond Science for Steering Chemical Reactions." The talk is part of the panel session titled "Attosecond Science in Chemical, Molecular Imaging, Spintronics, and Energy Science," which is scheduled for February 17, from 8:30 AM to 11:30 AM in Room 306 of the Hynes Convention Center.
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