INVESTIGADORES
ASCOLANI Hugo Del Lujan
artículos
Título:
Order-disorder phase transition of vacancies in surfaces: The case of Sn/Cu(001)-0.5 ML
Autor/es:
J.E. GAYONE; A. CARRERA; O. GRIZZI; S. BENGIO; E.A. SÁNCHEZ; J. MARTÍNEZ BLANCO; E.G. MICHEL; J. FUHR; H. ASCOLANI
Revista:
PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS
Editorial:
AMER PHYS SOC
Referencias:
Año: 2010 vol. 82 p. 354201 - 354205
ISSN:
0163-1829
Resumen:
We investigate the structural phase transition (3sqr2 x sqrt2)͒R45° ↔ (sqr2 x sqrt2)͒R45° of 0.5 ML Sn/Cu(100)͒ using a combination of scanning tunneling microscopy, time-of-flight direct-recoil spectroscopy, and Monte Carlo simulations. Cu vacancies are observed for both phases. At low temperature, Cu vacancies are ordered in a regular array of lines. At high temperature, Sn atoms occupy similar adsorption sites as at low temperature but Cu vacancies are disordered. We conclude that the atomistic mechanism behind the structural phase transition is an order/disorder transition driven by the Cu-vacancy entropy.
