Global transition path search for dislocation formation in Ge on Si(001)

Abstract

Global optimization of transition paths in complex atomic scale systems is addressed in the context of misfit dislocation formation in a strained Ge film on Si(001). Such paths contain multiple intermediate minima connected by minimum energy paths on the energy surface emerging from the atomic interactions in the system. The challenge is to find which intermediate states to include and to construct a path going through these intermediates in such a way that the overall activation energy for the transition is minimal. In the numerical approach presented here, intermediate minima are constructed by heredity transformations of known minimum energy structures and by identifying local minima in minimum energy paths calculated using a modified version of the nudged elastic band method. Several mechanisms for the formation of a 90° misfit dislocation at the Ge-Si interface are identified when this method is used to construct transition paths connecting a homogeneously strained Ge film and a film containing a misfit dislocation. One of these mechanisms which has not been reported in the literature is detailed. The activation energy for this path is calculated to be 26% smaller than the activation energy for half loop formation of a full, isolated 60° dislocation. An extension of the common neighbor analysis method involving characterization of the geometrical arrangement of second nearest neighbors is used to identify and visualize the dislocations and stacking faults.

References in corpus (3)

• Structure identification methods for atomistic simulations of crystalline materials
• Theoretical study of dislocation nucleation from simple surface defects in semiconductors
• Dislocation formation from a surface step in semiconductors: an ab initio study

Cited by in corpus (30)

• Assessment and optimization of the fast inertial relaxation engine (FIRE) for energy minimization in atomistic simulations and its implementation in LAMMPS
• Nudged elastic band calculations accelerated with Gaussian process regression
• Basal Slip in Laves Phases: the Synchroshear Dislocation
• From metallic glasses to nanocrystals: Molecular dynamics simulations on the crossover from glass-like to grain-boundary-mediated deformation behaviour
• Minimum energy path calculations with Gaussian process regression
• Ab Initio Models of Dislocations
• GeSn Defects and their Impact on Optoelectronic Properties: A Review
• Non-classical nucleation pathways in stacking-disordered crystals
• Unveiling the mechanisms of motion of synchro-Shockley dislocations in Laves phases
• Efficient Optimization Method for Finding Minimum Energy Paths of Magnetic Transitions
• Towards Large-Scale and Spatio-temporally Resolved Diagnosis of Electronic Density of States by Deep Learning
• Driving force induced transition in thermal behavior of grain boundary migration in Ni
• A simple local expression for the prefactor in transition state theory
• Atomistic View of Homogeneous Nucleation of Water into Polymorphic Ices
• Solid-phase silicon homoepitaxy via shear-induced amorphization and recrystallization
• Crystal structure identification with 3D convolutional neural networks with application to high-pressure phase transitions in SiO${}_2$
• Disruptive Atomic Jumps Induce Grain Boundary Stagnation
• A modified nudged elastic band algorithm with adaptive spring lengths
• Premelting layer during ice growth: role of clusters
• Transition dynamics and metastable states during premelting and freezing of ice surfaces
• Quantifying the contributions to diffusion in complex materials
• Spatially Local Estimates of the Thermal Conductivity of Materials
• Implicit Neural Representations for Chemical Reaction Paths
• Evaluation of Structural Properties and Defect Energetics in Al${}_x$Ga${}_{1-x}$N Alloys
• relentless: Transparent, reproducible molecular dynamics simulations for optimization
• First Principles Validation of Energy Barriers in Ni${}_{75}$Al${}_{25}$
• Designing binary mixtures of colloidal particles with simple interactions that assemble complex crystals
• Atomistic Simulations of H-Cu Vacancy Cosegregation and H Diffusion in Cu Grain Boundary
• Sliding Over Graphene Grain Boundaries: A Step Towards Macroscale Superlubricity
• Atomistic study of dislocation formation during Ge epitaxy on Si