Quantized Charge Pumping through a Carbon Nanotube Double Quantum Dot

TL;DR

This paper demonstrates quantized single-electron charge pumping in a carbon nanotube double quantum dot, showing precise control of electron transport up to 18 MHz and analyzing the effects of modulation parameters.

Contribution

It introduces a method for quantized charge pumping in a carbon nanotube double quantum dot using periodic potential modulation.

Findings

Successful single-electron pumping demonstrated

Quantized current observed up to 18 MHz

Rectification effects limit high-frequency operation

Abstract

We demonstrate single-electron pumping in a gate-defined carbon nanotube double quantum dot. By periodic modulation of the potentials of the two quantum dots we move the system around charge triple points and transport exactly one electron or hole per cycle. We investigate the pumping as a function of the modulation frequency and amplitude and observe good current quantization up to frequencies of 18 MHz where rectification effects cause the mechanism to break down.