(123d) Braiding Nanoscale Fibers Using Capillary Forces | AIChE

(123d) Braiding Nanoscale Fibers Using Capillary Forces


Manoharan, V. N. - Presenter, Harvard University
Electrical conductors that can carry frequencies of tens of GHz are needed for next-generation telecommunications networks. In principle, such conductors can be made from braided conducting filaments. However, maximizing the current-carrying capacity and minimizing loss requires each filament to have a diameter approximately equal to the skin depth, which is on the order of 1 micrometer at 10 GHz. Because such small filaments break easily, current manufacturing techniques cannot braid them. We have developed a technique to braid such small filaments using repulsive capillary forces. We attach microscale filaments to polymer "floats" that reside at a water-air interface. These floats pin the contact line such that, when they are placed in a hydrophilic container, the capillary force between the floats and the container walls is repulsive. As a result, the floats – and therefore the filaments – can be translated or rotated by moving the walls of the container. I will show how the containers can be designed and moved so as to braid the wires into arbitrary topologies. I will also discuss how the method scales to different filament sizes. The scaling is determined by the capillary forces on the floats and the elastic restoring forces in the filaments.

This research is in collaboration with Cheng Zeng, John Miles Faaborg, Yohai Bar Sinai, and Michael P. Brenner at Harvard University.