Dipartimento di Fisica, Università di Roma Tor Vergata, Via della Ricerca Scientifica, 1-00133 Roma, Italy.
J Phys Condens Matter. 2013 Feb 20;25(7):075802. doi: 10.1088/0953-8984/25/7/075802. Epub 2013 Jan 17.
By exploiting a fully three-dimensional finite-element modeling of strain fields, we investigate the spatial dependence of the elastic interaction energy between misfitting nanostructures beyond the point-dipole approximation. When interacting islands are finite in size, the detailed shape of the elastic strain field around and under the islands may convert the repulsive interactions, usually experienced between equal-sized islands, into an attractive basin between a large island and a population of neighboring clusters smaller than a critical size. The results of the simulations applied to large Ge islands grown on a Si(111) substrate have significant implications for the understanding of the strain-mediated coarsening of quantum dots around the islands.
通过对应变场的全三维有限元建模，我们研究了超出点偶极近似的失配位错纳米结构之间弹性相互作用能的空间依赖性。当相互作用的小岛有限大时，小岛周围和下方弹性应变场的详细形状可能会将通常在等大的小岛之间存在的排斥相互作用转化为在一个大的小岛和一群小于临界尺寸的相邻的小岛之间的吸引力盆地。应用于在 Si(111)衬底上生长的大 Ge 小岛的模拟结果对理解小岛周围的量子点的应变介导的粗化具有重要意义。
