کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9595061 1507973 2005 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Interplay of strain relaxation and chemically induced diffusion barriers: Nanostructure formation in 2D alloys
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Interplay of strain relaxation and chemically induced diffusion barriers: Nanostructure formation in 2D alloys
چکیده انگلیسی
We study the formation of nanostructures with alternating stripes composed of bulk-immiscible adsorbates during submonolayer heteroepitaxy. We evaluate the influence of two mechanisms considered in the literature: (i) strain relaxation by alternating arrangement of the adsorbate species and (ii) kinetic segregation due to chemically induced diffusion barriers. A model ternary system of two adsorbates with opposite misfit relative to the substrate, and symmetric binding is investigated by off-lattice as well as lattice kinetic Monte Carlo simulations. We find that neither of the mechanisms (i) or (ii) alone can account for known experimental observations. Rather, a combination of both is needed. We present an off-lattice model which allows for a qualitative reproduction of stripe patterns as well as island ramification in agreement with recent experimental observations for CoAg/Ru(0 0 0 1) [R.Q. Hwang, Phys. Rev. Lett. 76 (1996) 4757]. The quantitative dependencies of stripe width and degree of island ramification on the misfit and interaction strength between the two adsorbate types are presented. Attempts to capture essential features in a simplified lattice gas model show that a detailed incorporation of non-local effects is required.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface Science - Volume 586, Issues 1–3, 20 July 2005, Pages 157-173
نویسندگان
, , , ,