Martinsons M, Schmiedeberg M
Institut für Theoretische Physik I, Friedrich-Alexander Universität Erlangen-Nürnberg, Staudtstraße 7, 91058 Erlangen, Germany.
J Phys Condens Matter. 2018 Jun 27;30(25):255403. doi: 10.1088/1361-648X/aac503. Epub 2018 May 15.
The growth of quasicrystals, i.e. structures with long-range positional order but no periodic translational symmetry, is more complex than the growth of periodic crystals. By employing Brownian dynamics simulations in two dimensions for colloidal particles that interact according to an isotropic pair potential with two incommensurate lengths, we study the growth of quasicrystalline structures by sequentially depositing particles at their surface. We quantify the occurrence of quasicrystalline order as a function of the temperature and the rate of added particles. In addition, we explore defects like local triangular order or gaps within the quasicrystalline structure. Furthermore, we analyze the shapes of the surfaces in grown structures which tend to build straight lines along the symmetry axes of the quasicrystal. Finally, we identify phasonic flips which are rearrangements of the particles due to additional degrees of freedom. The number of phasonic flips decreases with the distance to the surface.
准晶体（即具有长程位置有序但无周期性平移对称性的结构）的生长比周期性晶体的生长更为复杂。通过对根据具有两个非相称长度的各向同性对势相互作用的胶体粒子进行二维布朗动力学模拟，我们研究了通过在准晶体表面依次沉积粒子来生长准晶体结构的过程。我们将准晶序的出现量化为温度和添加粒子速率的函数。此外，我们还探索了准晶体结构中的缺陷，如局部三角序或间隙。此外，我们分析了生长结构中表面的形状，这些表面倾向于沿着准晶体的对称轴形成直线。最后，我们识别出了声子翻转，它是由于额外的自由度导致的粒子重排。声子翻转的数量随着与表面距离的增加而减少。
