Gate induced crossover between Fabry–Pérot and quantum dot behavior in a single walled carbon nanotube hole transistor

Abstract

Gate induced crossover between Fabry–Pérot and quantum dot behavior in a single walled carbon nanotube (SWCNT) hole transistor is observed. The SWCNT transistor that can operate as a resonant tunneling transistor (RTT) and also as a single-hole transistor (SHT) using SWCNT as channel is fabricated. When negatively high voltage is applied to the gate electrode, the SWCNT transistor shows RTT characteristic, e.g., Fabry–Pérot quantum interference pattern. While, when negatively low voltage is applied to the gate electrode, the SWCNT transistor shows SHT characteristic, e.g., Coulomb diamond characteristic. The transition between RTT and SHT is achieved by modulating the coupling strength between the electrode and the quantum island using gate voltage change. Schottky barriers at the contact between the SWCNT and the electrodes act as tunneling barriers. The thicknesses of the tunneling barriers are modulated by the gate voltage change, and the strength of the coupling between the electrode and quantum island is also changed. The characteristics of the convertible transistor can be observed up to 100K. Moreover, the channel length dependence is observed.