Exploring the subsurface atomic structure of the epitaxially grown phase change material Ge 2 Sb

J. Kellner, G. Bihlmayer, V. L. Deringer3,∗ M. Liebmann, C. Pauly, A. Giussani4,† J. E. Boschker, R. Calarco, R. Dronskowski, and M. Morgenstern1‡ II. Physikalisches Institut B and JARA-FIT, RWTH Aachen University, D-52074 Aachen, Germany Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52428 Jülich, Germany Institute of Inorganic Chemistry, RWTH Aachen University, D-52074 Aachen, Germany and Paul Drude Institut für Festkörpelektronik Berlin, D-10117 Berlin, Germany (Dated: September 28, 2017)