Size evolution of silver nanowires under thermal field and its application in nano-healing: A molecular dynamics study

Laser-induced nano-healing plays a pivotal role in repairing structural defects in devices, primarily attributed to localized thermal fields generated by photothermal effects, which reduce nanogap sizes. However, the phenomenon of nanomaterial contraction into spheres under thermal fields indicates that the underlying mechanisms of nano-healing under thermal influence remain incompletely understood. This study employs molecular dynamics simulations to investigate the size evolution of silver nanowires under thermal fields, aiming to explore the effects of temperature on nanomaterial size changes and to further elucidate the mechanisms of nano-healing applications. The findings reveal that temperatures during the surface melting phase, below the melting point, promote the attainment of larger axial sizes in silver nanowires. The axial dimensions of silver nanowires are influenced not only by temperature-induced lattice spacing but also by the transport of atoms toward the central regions of end faces driven by surface melting. The study demonstrates that temperatures during the surface melting phase are more favorable for the healing of nanogaps, with higher temperatures enhancing the surface diffusion healing of nanoscale pits. These results provide valuable insights into the utilization of thermal fields for nano-healing and the subsequent repair of device defects.