A new extreme-ultraviolet (UV) laser source, developed at the University of British Columbia (UBC), enables time-resolved photoemission spectroscopy, a technique for visualizing electron scattering processes at ultrafast timescales.
Photoemission spectroscopy can record, frame-by-frame, how an electron interacts with certain atomic vibrations in a solid, capturing a process that can cause electrical resistance in some materials and macroscopic quantum phenomena such as superconductivity in others. A scattering event between the vibration and the electron, called a phonon, can cause the electron to change both its direction and its energy. Such electron-phonon interactions are the basis of many exotic phases of matter.