Year: 2020
Type: article
Abstract: thesis problem.Verified with experimental data theoretical models allow to define the critical parameters of the NWs that lead to defect generation.Thus, many researchers to date have focused on the development of theoretical models describing the defect structure of NWs.Since the early 2000s, the first theoretical studies of misfit strains and mechanisms of their relaxation through generation of various defects in axially-[16-22] and radially-inhomogeneous (core-shell) [13,14, composite NWs have been published.A large part of these works was done within various continuum approaches [21,23,24,[26][27][28][29]31,32,34,37,[44][45][46][48][49][50]53,55,58,[61][62][63] and aimed at the calculation of critical conditions of relaxation by defect generation.Referenced theoretical models can be divided into two groups.For both groups, the authors have used the energetic approach, considering the energy change due to the formation of the defects.To the first group we include the models, considering the nucleation of a final configuration of the defects, such as dislocations [23,27,45,49], dislocation dipoles [32], dislocation loops [26,27,29,31,34,37,44,63]; to the second group we include the models, considering the energy barriers for nucleation and evolution of the defect configuration, such as dislocations and their dipoles [61], and dislocation loops [46,48,58,[60][61][62]. QUASI-EQUILIBRIUM ENERGY APPROACH FOR CALCULATING THE CRITICAL CONDITIONS OF MD GENERATION IN CORE-SHELL NWsLet us consider in more detail the quasi-equilibrium energy approach suggested for core-shell NWs in [23] and used in the models of the first group.In applying to MDs at interfaces in flat misfitting heterostructures like a thin epilayer on a semi-infinite substrate, this approach was invented by Frank and Van der Merwe [64] and adopted in the simplest macroscopic form by Matthews [65].Since that time, many different modifications of this approach were suggested (see, for example, some papers [66-81] and books [82][83][84]).The authors of [23] used the approach variant suggested earlier by Gutkin and Romanov [67,73].
Language: English
Subfield: Metals and Alloys
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
Award: G4639041176
OpenAlex ID: W3140848331