Supplementary material for the paper

The I-V curves of the CNT-CNT connections for reference

Figure s6 gives the information of the electrical property in the CNT-CNT contact without fullerene. Comparing to situations with a fullerene between them, the CNT-CNT connections show increased current level (increased ~20% at corresponding voltages). As a matter of fact, although increased current level was normally observed in the CNT-CNT contact, the I-V curves of the CNT-CNT contact were also affected by the contact geometry. Simply, larger contact area shows accordingly higher current level and vise versa. The detailed discussion about this is out of the extent of this paper.

Figure s6 the I-V curves of the CNT-CNT connection without fullerene between them. (a) Corresponds to the situation shown in figure s3 and (b) corresponds to the situation shown in figure s2. I-V curves noted with different numbers correspond to different scans. Inset TEM figures present the structure of the CNT-CNT connections in different I-V scans, as indicated. Bar= 10 nm. Arrows point out the contact sites between the two CNTs.

4.