Controllable growth of metallic nano-helices at room temperature conditions

摘要

We report on a method to produce multiple-pitch, regularly shaped, aligned, and freestanding metallic nano-helices at room temperature. This method overcomes the limitations of the standard glancing angle deposition approach through a heat-management technique devoid of active substrate cooling and is even applicable for metals with low melting point, that is, high surface adatom diffusion. The structural quality and optical activity response of these metal nano-helices are comparable to state of the art helices produced by employing substrates cooled down to cryogenic temperatures.