Electrostically defined few-electron double quantum dot in silicon

TL;DR

This paper reports the fabrication and characterization of a silicon-based double quantum dot device with tunable inter-dot coupling, demonstrating clear resonant tunneling and energy spectrum control through low-temperature transport measurements.

Contribution

It introduces a MOS-compatible fabrication method for a tunable silicon double quantum dot with detailed spectroscopic analysis.

Findings

Tunable inter-dot coupling over a wide range.

Observation of resonant single-electron tunneling.

Clear charge stability diagram and energy spectrum control.

Abstract

A few-electron double quantum dot was fabricated using metal-oxide-semiconductor(MOS)-compatible technology and low-temperature transport measurements were performed to study the energy spectrum of the device. The double dot structure is electrically tunable, enabling the inter-dot coupling to be adjusted over a wide range, as observed in the charge stability diagram. Resonant single-electron tunneling through ground and excited states of the double dot was clearly observed in bias spectroscopy measurements.