Nanoscale physics

Monte-Carlo modeling of crystal growth of periodic shells
on one-dimensional substrates
Gorshkov V.N., Tereshchuk V.V.
National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute".   37, Prosp.Peremohy, Kyiv, Ukraine, 03056. 
E-mail: vn.gorshkov@gmail.com

Nanosize morphology, especially its emergence in surface growth by processes of attachment and restructuring of deposits formed by atoms, ions, or molecules, is an active field of research driven by numerous applications. In a recent work [1], the authors “report a general method of synthesizing diameter-modulated core–shell nanowires whose morphologies are tunable over an unprecedented range”.
In our work we have numerically investigated the governing mechanisms that are responsible for formation of nanoclusters on the nanowire with diamond-like lattice structure (Si, Ge), which is observed in [1] when free atoms deposit on the nanowire surface.
One of the findings has been that the growth process depends on the orientation of the initial nanowire shape with respect to the lattice planes of its internal crystal structure. As a result of this dependency, the shape of the growing shells can be essentially different (See the Fig. above where both the results of numerical simulations and physical experiments are presented.) 
It is shown that the pitch of the periodic nanowire diameter-modulation may be controlled by changing the system temperature and the free atom concentration in the surrounding space.

1.	R. W. Day, M. N. Mankin, Ruixuan Gao et al. Plateau–Rayleigh crystal growth of periodic shells on one-dimensional substrates // Nature Nanotechnology -2015.-10, -P.  345–352.