  Carbon nanotube (CNT) wires approach copper's specific conductivity and
surpass carbon fiber's strength, with further improvement anticipated with
greater aspect ratios and incorporation of dopants with long-range structural
order. Fullerenes assemble into multitudes of process-dependent supramolecular
crystals and, while initially insulating, they become marginally conductive (up
to 0.05 MSm$^{-1}$) and superconductive ($T_c=18^\circ$K with K and 28$^\circ$K
with Rb) after doping. These were small (100's $\mu$m long), soft (hardness
comparable to indium), and typically unaligned, which hindered development of
fullerene based wires. Individual fullerenes were previously incorporated into
CNT fibers, although randomly without self-assembly into supramolecules. Here,
a simple variation in established CNT acid extrusion creates a fiber composed
of uniaxial chains of aligned fullerene supramolecules, self-assembled between
aligned few-walled CNT bundles. This will provide a testbed for novel fullerene
wire transport and prospects in CNT wire advancement.

Materials Science