A model for the Auger mediated quantum sticking of positrons at surfaces

ORAL

Abstract

We present a model of an efficient mechanism for positron sticking to surfaces termed here Auger mediated quantum sticking (AMQS).The AMQS process is closely related to the Auger de-excitation of atoms or molecules [1] near surfaces. We suggest that the positron excites an electron-hole pair while dropping to the surface state resulting in emission of a secondary electron. The relevant parameters of the model are the positron binding energy at the surface, the work function, the Fermi energy and the electron density of states. Our estimate for the reaction rates and the sticking probabilities are compared to detailed calculations by Walker et al. [2]. \\[4pt] [1] H. D. Hagstrum, Phys. Rev. \textbf{96}, 336 (1954); B. Barbiellini and P.M. Platzman, New J. Phys. \textbf{8}, 20 (2006). \newline [2] A. B. Walker et al. , ~Phys. Rev. B \textbf{46}, 1687 (1992).

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Authors

  • S. Mukherjee

    University of Texas Arlington

  • Manori Nadesalingam

    UT dallas

  • Paul Guagliardo

    University of Western Australia

  • Anthony Sergeant

    University of Western Australia

  • B. Barbiellini

    Northeastern Univ. (NU), Northeastern University, Northeastern U.

  • Alexander Weiss

    University of Texas Arlington, Univ of Texas at Arlington, Department of Physics, UTA, TX, Physics Department, University of Texas at Arlington, Dept. of Physics, U T Arlingto

  • Nail Fazleev

    University of Texas Arlington, University of Texas at Arlington

  • J. Williams

    University of Western Australia