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arXiv · 0912.0409

Multi-terminal quantum transport through a single benzene molecule: Evidence of a Molecular Transistor

Santanu K. Maiti
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Abstract

We explore multi-terminal quantum transport through a benzene molecule threaded by an Aharonov-Bohm flux $ϕ$. A simple tight-binding model is used to describe the system and all the calculations are done based on the Green's function formalism. With a brief description of two-terminal quantum transport, we present a detailed study of three-terminal transport properties through the benzene molecule to reveal the actual mechanism of electron transport. Here we numerically compute the multi-terminal conductances, reflection probabilities and current-voltage characteristics in the aspects of molecular coupling strength and magnetic flux $ϕ$. Most significantly we observe that, the molecular system where the benzene molecule is attached to three terminals can be operated as a transistor, and we call it a molecular transistor. This aspect can be utilized in designing nano-electronic circuits and our investigation may provide a basic framework to study electron transport in any complicated multi-terminal quantum system.

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Santanu K. Maiti. 2009-12-02. Multi-terminal quantum transport through a single benzene molecule: Evidence of a Molecular Transistor. https://doi.org/10.1016/j.ssc.2010.05.025

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