Surface Diffusion Anomaly near a Substrate Phase Transition: H on <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi><mo>(</mo><mn>100</mn><mo>)</mo></math></span>

Lei Cai; M. S. Altman; E. Granato; T. Ala-Nissila; S. C. Ying; Xudong Xiao

doi:10.1103/PhysRevLett.88.226105

Surface Diffusion Anomaly near a Substrate Phase Transition: H on $W (100)$

Lei Cai, M. S. Altman, E. Granato, T. Ala-Nissila, S. C. Ying, and Xudong Xiao

Phys. Rev. Lett. 88, 226105 – Published 20 May 2002

Abstract

Using a linear optical diffraction method, we have experimentally studied the long predicted diffusion anomalous behavior for $H / W (100)$ near the reconstructive phase transition of the $W (100)$ substrate. This anomaly manifests itself in the form of a strong dip in the diffusion coefficient $D$ at the transition temperature $T_{C}$ . We interpret the strong reduction of $D$ as a result of the diverging friction damping near the transition. The finite dip in $D$ instead of a vanishing $D$ at $T_{C}$ also demonstrates the importance of the non-Markovian (memory) deviation from the simple instantaneous damping picture.

Received 25 January 2002

DOI:https://doi.org/10.1103/PhysRevLett.88.226105

Authors & Affiliations

Lei Cai¹, M. S. Altman¹, E. Granato², T. Ala-Nissila^3,4, S. C. Ying³, and Xudong Xiao^1,*

¹Department of Physics, The Hong Kong University of Science and Technology, Hong Kong, SAR, China
²Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, SP Brazil
³Department of Physics, Brown University, Providence, Rhode Island 02912
⁴Helsinki Institute of Physics and Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT, Espoo, Finland