Y Sato

Publications (2)9.54 Total impact

• Article: Morphology of the Cu2O surface oxide phase formed on Cu(100) at high temperature

  C. L. H. Devlin, Y. Sato, S. Chiang
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  ABSTRACT: We have observed the nucleation and growth of the Cu ₂ O surface oxide on a Cu(100) surface at 870 K using low energy electron microscopy. Nucleating on a surface exhibiting the ( √ 2 ×2 √ 2 )R45° -O overlayer, this phase caused the overall step morphology to change from long, mostly straight narrow-terraced step bunches to broad, deeply curved terraces with more highly bunched steps. Using x-ray photoelectron spectroscopy, we have measured an upper bound of 2.6 ML (monolayer) for the surface oxygen coverage at which we observed this oxide phase. The lattice constant of the observed oxide phase matches that of the (111) face of Cu ₂ O . We postulate that the oxide does not form epitaxially on this surface at this temperature due to interactions with the centered rectangular phase of oxygen, which provides a nearly hexagonal template for the Cu ₂ O (111) hexagonal structure.
  Journal of Applied Physics 07/2009; · 2.17 Impact Factor
• Article: Spontaneous domain switching during phase separation of Pb on Ge(111).

  Y Sato, S Chiang, N C Bartelt
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  ABSTRACT: Using low-energy electron microscopy (LEEM), we have discovered a novel phase separation mechanism for Pb on Ge(111). When the low Pb coverage (1 x 1) phase coexists with the high coverage beta phase, the surface consists of approximately 100 nm sized domains that spontaneously switch from one phase to the other. We argue this striking mechanism occurs because nanometer-scale domains can have density fluctuations comparable to the density difference between the two phases.
  Physical Review Letters 09/2007; 99(9):096103. · 7.37 Impact Factor