Gate-Induced Cross-Over between Fabry–Perot Interference and Coulomb Blockade in a Single-Walled Carbon Nanotube Transistor with Double-Gate Structure

Abstract

The gate-induced cross-over between Fabry–Perot interference and Coulomb blockade characteristics in a single-walled carbon nanotube (SWNT) transistor are observed. The behaviors of Fabry–Perot interference and Coulomb blockade are controlled by the control-gate and observed by the sweep-gate. When a negatively high voltage is applied to the control-gate electrode, the SWNT transistor showed a resonant tunneling transistor (RTT) characteristic, e.g., a Fabry–Perot quantum interference pattern. However, when a negatively low voltage is applied to the control gate electrode, the SWNT transistor showed a single-hole transistor (SHT) characteristic, e.g., a Coulomb diamond characteristic. The transition between RTT and SHT is achieved by modulating the coupling strength between the source and drain electrodes and the quantum island using control-gate voltage change. Schottky barriers at the contact between the SWNT and the source and drain electrodes act as tunneling barriers. The thicknesses of the tunneling barriers are modulated by the control-gate voltage change, and the strength of the coupling between the source and drain electrode and the quantum island is also modulated.