JERK, an event-based Kinetic Monte Carlo model to predict microstructure evolution of materials under irradiation

Abstract

2005) JERK, an event-based Kinetic Monte Carlo model to predict microstructure evolution of materials under irradiation, Philosophical Magazine, 85:4-7, 549-558To link to this article: http://dx.JERK is a Kinetic Monte Carlo model which aims at describing the evolution of materials under irradiation over large time and length scales. The evolution is calculated by collecting only those events which actually modify the objects making up the microstructure (defect clusters, various complexes, dislocations), by sampling their probability of occurrence, deciding in view of the chosen delays whether the events will take place or not within a given time interval. The details of the atomic transport are ignored and the jumps of mobile species are bunched into trajectories, which comply with continuous diffusion laws. After some tuning, the increase in efficiency over a Kinetic Monte Carlo procedure which processes each jump event after another should be noticeable.

Ion and electron irradiation-induced effects in nanostructured materials

“…In atomic KMC ͑AKMC͒ simulations, all atom coordinates are included but only one or a few defects ͑typically vacancies͒ at a time are moving. 251 In other modifications of the method, only the mobile defects are followed, and the lattice atoms are not explicitly described at all ͑such methods are known as object, reaction, event, 252 or first-passage 253 KMC͒. Since only the objects of interest are simulated, this allows for simulation of macroscopic time ͑up to several hours͒ and length scales.…”

Advanced Computational Materials Science: Application to Fusion and Generation IV Fission Reactors (Workshop Report)

“…Systems of larger dimension (µm 3 ) and comprising complex objects can be explored with the help of Event-Based KMC models, in which the MC algorithm is not applied to individual atomic jumps but to the probability of impingement or dissociation of populations of mobile defects and immobile objects [40]. This is possible at the expense of detailed spatial localization, which is no longer at the atomic scale.…”

Modeling Microstructure and Irradiation Effects

“…In OKMC models, [23,24,224] defect migration jumps are explicitly treated and reactions occur when two defects (mobile objects) meet each other, or meet traps or sinks. EKMC models [25,26] do not treat individual migration jumps explicitly, and only reactions (events) between objects drive the evolution of the system. Contrarily to ab-initio or MD codes, no commercial or public codes are openly available, and each group develops the software needed for its own purpose.…”

“…Following the suggestion of Reference 21, we use the term MFRT here. KMC methods can be applied to objects (OKMC [22][23][24] ), events (EKMC [25,26] ), or atoms (AKMC [27][28][29][30][31][32][33][34][35][36] ) in a specific volume. Both KMC and MFRT can be globally defined as coarse-grained models, because atoms are not explicitly treated in either except in the atomistic (or lattice) KMC, i.e., the AKMC.…”

“…KMC methods can be applied to study the evolution of systems of mobile species, such as atoms in atomistic KMC [27][28][29][30][31][33][34][35][36]222] or larger defects, formed, for instance, under irradiation in so-called coarser-grained KMC models. [22][23][24][25][26]223] Many coarse-grained KMC models were formulated to describe the long-term evolution of the primary damage produced by irradiation. In OKMC models, [23,24,224] defect migration jumps are explicitly treated and reactions occur when two defects (mobile objects) meet each other, or meet traps or sinks.…”