Accelerating a free electron with a laser has been a longtime goal of solid-state physicists.
David Cline, a distinguished professor in the UCLA Department of Physics and Astronomy, and Xiaoping Ding, an assistant researcher at UCLA, have conducted research at Brookhaven National Laboratory in New York and have established that an electron beam can be accelerated by a laser in free space.
This has never been done before at high energies and represents a significant breakthrough, Cline said, adding that it also may have implications for fusion as a new energy source. (more…)
Studies by Berkeley Lab scientists of electron beam quality in laser plasma accelerators include novel tests for slice-energy spread
Part Two: Slicing through the electron beam
Wim Leemans of Berkeley Lab’s Accelerator and Fusion Research Division heads LOASIS, the Laser and Optical Accelerator Systems Integrated Studies, an oasis indeed for students pursuing graduate studies in laser plasma acceleration (LPA). Among the most promising applications of future table-top accelerators are new kinds of light sources, in which their electron beams power free electron lasers.
“If our LPA electron bunches had good enough quality for free electron lasers – and were really only femtoseconds long – we should see a particular kind of radiation called coherent optical transition radiation, or COTR,” Leemans says. “So I assigned my doctoral student Chen Lin, a graduate of Peking University and now a postdoc there, to find it.” (more…)
Berkeley Scientists Create Graphene Liquid Cells for Electron Microscopy Studies of Nanocrystal Formation
They won’t be coming soon to a multiplex near you, but movies showing the growth of platinum nanocrystals at the atomic-scale in real-time have blockbuster potential. A team of scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley has developed a technique for encapsulating liquids of nanocrystals between layers of graphene so that chemical reactions in the liquids can be imaged with an electron microscope. With this technique, movies can be made that provide unprecedented direct observations of physical, chemical and biological phenomena that take place in liquids on the nanometer scale. (more…)
‘Wonder material’ may hold key to fast, inexpensive genetic sequencing
Look at the tip of that old pencil in your desk drawer, and what you’ll see are layers of graphite that are thousands of atoms thick. Use the pencil to draw a line on a piece of paper, and the mark you’ll see on the page is made up of hundreds of one-atom layers.
But when scientists found a way—using, essentially, a piece of ordinary sticky tape—to peel off a layer of graphite that was just a single atom thick, they called the two-dimensional material graphene and, in 2010, won the Nobel Prize in physics for the discovery. (more…)
