image: These are beam profiles of free electron vortices. The beams were created by diffraction from a nanofabricated hologram in a transmission electron microscope. The multiple hollow electron beams to either side of the bright central beam are high order electron vortices with large vortex cores, and show up as rings when projected onto an imaging detector. Each electron in these beams possesses quantized orbital angular momentum -- 25h quanta per electron in the first-order beams immediately to the side of the central beam, and 50h, 75h, and 100h per electron in the second-, third-, and fourth-order beams, respectively. This image relates to an article that appeared in the Jan. 14, 2011, issue of Science, published by AAAS. The study, by Dr. McMorran at National Institute of Standards and Technology in Gaithersburg, Md., and colleagues was titled, "Electron Vortex Beams with High Quanta of Orbital Angular Momentum." view more
Credit: Image © B. McMorran, A. Herzing/NIST