Optically controlled local nanosoldering of metal nanowires

Abstract

Nanojoining (including nanowelding, nanosoldering, etc.) of metal nanomaterials offers the opportunity of constructing complex structures and advanced functional devices at the nanoscale. In comparison with nanowelding, nanosoldering does not involve the melting of base metal and shows considerable mechanical strength and good thermal and electrical conductivity. Here, an optically controlled local nanosoldering technique, which ensures the nanostructures to be bonded while their original structural integrity is retained, is proposed and demonstrated. Typical elemental devices (V-shaped, T-shaped, and X-shaped nanostructures) are formed with this nanosoldering technique. The conductivity of one V-shaped junction is enhanced by 500 times after nanosoldering. This facile nanosoldering technique provides an avenue to locally manipulate light, charge, heat, and mass transport at the nanoscale and is thereby expected to benefit the development of nanophotonics and nanoelectronics.