16. July 2019
BREMEN-OLDENBURG RELATIVITY SEMINAR
Location: ZARM, University of Bremen, Room 1730
When: 16.07.2019, 11:00 c.t.
Speaker: Prof. Dr. Andrey Surzhikov (PTB, Braunschweig)
Title: Scattering of relativistic vortex electrons
Abstract:Studies on the scattering of relativistic electrons by atoms and ions have a very long tradition both in theory and experiment. During the recent years, special emphasis in these studies has been placed on the so-called twisted (or vortex) electrons. The beams of twisted electrons, that carry a nonzero projection of the orbital angular momentum (OAM) upon their propagation direction, serve today as a valuable tool for probing the magnetic properties of materials at the nano- and even atomic scale. In this contribution, therefore, we re-visit two fundamental processes involving vortex beams: electron-atom and electron-electron scattering. We derive the differential cross sections for both processes and discuss how these cross sections differ from those obtained for the usual plane-wave electrons. Based on this analysis we will show how vortex electrons may shed more light on the relativistic and magnetic effects in Mott and Møller scattering, and can provide access to the Coulomb phase; a quantity which plays an important role in various collision processes but which cannot be observed in usual, plane-wave-experiments.