Interaction between laser and nanomaterials

1. Near-field electromagnetic interaction

For understanding interaction between nanomaterials and laser, the dynamics of the electromagnetic wave should be analyzed in the region which is much shorter than the wavelength of incident laser. These following figures shows (a) the electric field and (b) Joule heating source obtained by solving Maxwell’s equation based on finite element method.

2. Structural transformation of carbon nanotubes

Individual carbon nanotubes (CNTs) have outstanding physical properties, but the bulk properties of CNTs network have tendency to be significantly degraded due to their weak interaction between CNTs. Laser irradiation can heal the defect of CNTs and enhance bond strength between CNTs by effectively modifying structures of CNTs.

3. Laser nanowelding of Silver nanowires

Silver nanowire (AgNW) networks have attracted a lot of attention as a promising alternative to indium tin oxide film due to their excellent electrical, optical, and mechanical properties. The electrical conduction of nanowire network is dominated by the NW-NW junction resistance. There is an emerging need to join silver nanowire junctions is a highlight topic of fundamental and technological interests in scalable fabrication of future electronics. When the light is incident to crossing two AgNWs, field enhancement which occurs in the nanoscale gap between the AgNWs can weld them together. The optical welding technique has a great advantages to induce the localized heat generation at the junction compared to thermal annealing