Regensburg 2004 – wissenschaftliches Programm
O 25.8: Vortrag
Dienstag, 9. März 2004, 17:30–17:45, H39
Continuous Phase Transition of Surface Reconstructions Investigated by X-ray Scattering: Theory and Experiment — •Frank Grosse1, Bernd Jenichen2, Wolfgang Braun2, Vladimir M. Kaganer2, Dilip K. Satapathy2, X. Guo2, and Klaus H. Ploog2 — 1Institut für Physik der Humboldt-Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany — 2Paul-Drude-Institut für Festkörperelektronik Hausvogteiplatz 5-7, 10117 Berlin, Germany
Atomistic simulations for the reconstruction transition on the InAs(001) surface are performed on the basis of ab initio density functional calculations . A continuous surface phase transition of the As-rich β2(2×4) reconstruction to the α2(2×4) reconstruction is predicted leading to a mixture of both reconstructions. The atomic coordinates of the simulation cells are used to calculate the X-ray diffraction intensity employing kinematic theory. The equilibrium properties and kinetic effects due to change in temperature as well as As-pressure are discussed. Experiments performed at BESSY (Berlin) allow an in situ measurement and structure analysis of the reconstruction phase transition and are in agreement with the theoretical predictions.  F. Grosse, W. Barvosa-Carter, J.J. Zinck, M. Wheeler, and M.F. Gyure. Phys. Rev. Lett. 89, 116102 (2002); F. Grosse and M. Gyure. Phys. Rev. B. 66, 075320 (2002).