Novel conductance step in carbon nanotube with wing-like zigzag graphene nanoribbons**Project supported by the National Natural Science Foundation of China (Grant No. 10947004) and the Government Scholarship for Overseas Studies of Jiangsu Province, China.

Abstract

Connecting one armchair carbon nanotube (CNT) to several zigzag graphene nanoribbons (ZGNRs) we find that the topologically-protected edge states of ZGNRs and the massless Dirac particle inherited from CNT still hold from the analysis of the band structure and the edge state. Furthermore, the lowest conductance step at the valley bottom increases proportionally with increasing the number of ZGNR wings. A novel conductance step of a peak occurs in the valley, which is two steps higher than the lowest step at the valley bottom. In addition, with increasing the number of ZGNR wings the width of the novel conductance step becomes narrow.