Multi-Back-Gate Control of Carbon Nanotube Double-Quantum Dot

摘要

We have fabricated single-walled carbon nanotube (SWNT) quantum dot device with local multi-back gates, in which a SWNT is not surrounded by an insulator or gate electrodes. The charge states of multi-quantum dots, which are separated by an intrinsic defect of a SWNT, can be independently controlled by applying two local back gates. The charge stability diagram changes depending on the gate voltage range, which changes the interdot coupling between two dots. Furthermore, a honeycomb charge stability diagram corresponding to an intermediately coupled double-quantum dot is also observed.