Structural exploration of thin-film oxide interfaces via 'simulated amorphisation and recrystallisation'

Realistic atomistic simulation models of interfaces must include a sufficiently large simulation cell to accommodate the incommensurate relationship between the lattice parameters of the two materials, and include misfit-induced defects such as dislocations. In addition, the final structure must not be influenced artificially by the starting structure. Here we present a methodology, which satisfies such demands by performing large-scale atomistic simulations of thin-film oxide interfaces, which approach the meso-scale and involve amorphisation and recrystallisation of the thin film. The methodology is applied to the SrO/MgO(0 0 1) system, which was used as a model system representative of supported materials associated with a high lattice misfit. The final MgO(0 0 1) supported SrO thin-film structures comprise many dislocations (including mixed screw edge and pure edge), defects, reduced interfacial ion densities, commensurate domains and low angle rotated domains. (C) 2001 Elsevier Science B.V. All rights reserved.