Characterization of aperiodic and periodic thin Cu films formed on the five-fold surface of i-Al70Pd21Mn9 using medium-energy ion scattering spectroscopy

The elucidation of the local atomic structure of a pseudomorphic film of Cu deposited on the five-fold surface of i-Al70Pd21Mn9using medium-energy ion scattering spectroscopy is reported. Monte Carlo calculations, using the VEGAS code, have been utilized to simulate the blocking of 100 keV He+ ions scattered from the overlayer. The coordinates of the Cu atoms in the overlayer derived from this procedure are consistent with a structure occurring in five rotational domains. Each domain consists of nanoscale strips of fcc Cu(100) with the ⟨110⟩ azimuth aligned along the five-fold directions of the quasicrystalline substrate. The strips are arranged according to a one-dimensional Fibonacci sequence with long and short widths related by the golden mean τ. Upon annealing the film transforms to an alloyed structure composed of five orientational domains of fcc material with the (110) axis perpendicular to the surface. Disciplines Condensed Matter Physics | Metallurgy Comments This article is from Physical Review B 74 (2006): 035429, doi:10.1103/PhysRevB.74.035429. Authors J. A. Smerdon, J. Ledieu, R. McGrath, T. C. Q. Noakes, P. Bailey, M. Draxler, C. F. McConville, Thomas A. Lograsso, and A. R. Ross This article is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/ameslab_pubs/72 Characterization of aperiodic and periodic thin Cu films formed on the five-fold surface of i-Al70Pd21Mn9 using medium-energy ion scattering spectroscopy J. A. Smerdon, J. Ledieu,* and R. McGrath Surface Science Research Centre, The University of Liverpool, Liverpool L69 3BX, United Kingdom T. C. Q. Noakes and P. Bailey CCLRC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom M. Draxler and C. F. McConville Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom T. A. Lograsso and A. R. Ross Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA Received 28 September 2005; revised manuscript received 30 March 2006; published 27 July 2006 The elucidation of the local atomic structure of a pseudomorphic film of Cu deposited on the five-fold surface of i-Al70Pd21Mn9 using medium-energy ion scattering spectroscopy is reported. Monte Carlo calculations, using the VEGAS code, have been utilized to simulate the blocking of 100 keV He+ ions scattered from the overlayer. The coordinates of the Cu atoms in the overlayer derived from this procedure are consistent with a structure occurring in five rotational domains. Each domain consists of nanoscale strips of fcc Cu 100 with the 110 azimuth aligned along the five-fold directions of the quasicrystalline substrate. The strips are arranged according to a one-dimensional Fibonacci sequence with long and short widths related by the golden mean . Upon annealing the film transforms to an alloyed structure composed of five orientational domains of fcc material with the 110 axis perpendicular to the surface. DOI: 10.1103/PhysRevB.74.035429 PACS number s : 61.44.Br, 68.35.Bs, 68.37.Ef