A high transmission wave-guide wire network made by self-assembly

Polymer self-assembly of a 3D continuous gyroid morphology was replicated into a network consisting of hollow gold struts. This was achieved by first replicating a gyroid structured film into nickel. The Ni network was employed as an electrode for electrochemical Au deposition, followed by the removal of Ni. The resulting hollow network of plasmonic gold exhibited a substantial optical transmission enhancement by a factor of nearly 3, compared to a network of full Au struts. The overall transmission across the hollow wave-guide morphology depends sensitively on the wall-thickness of the hollow struts down to 1 nm. The dramatic transmission increase arises from an interplay of three mechanisms: (1) the additional number of modes propagating through the wave-guide structure, (2) the increased efficiency of light in-coupling, and (3) a reduction of dissipation by decreasing the Au-volume experienced in plasmon mode propagation.