A pure-carbon ring transistor: The role of topology and structure

TL;DR

This paper investigates the rectification and transmission properties of a carbon nanotube ring transistor, highlighting how topology and structure influence electronic behavior, with results validated by experiments and revealing novel conductance patterns.

Contribution

It provides new insights into how ring topology and structural features affect the electronic transmission and rectification in CNT ring transistors, distinguishing topological effects from structural confinement.

Findings

Linear conductance shows a 'chessboard'-like pattern.

Zero-lines in conductance are observed.

Structural properties are distinguished from topological effects.

Abstract

We report results on the rectification properties of a carbon nanotube (CNT) ring transistor, contacted by CNT leads, whose novel features have been recently communicated by Watanabe et al. [Appl. Phys. Lett. 78, 2928 (2001)]. This paper contains results which are validated by the experimental observations. Moreover, we report on additional features of the transmission of this ring device which are associated with the possibility of breaking the lead inversion symmetry. The linear conductance displays a "chessboard"-like behavior alternated with anomalous zero-lines which should be directly observable in experiments. We are also able to discriminate in our results structural properties (quasi-onedimensional confinement) from pure topological effects (ring configuration), thus helping to gain physical intuition on the rich ring phenomenology.