A gate-defined silicon quantum dot molecule

TL;DR

This paper demonstrates a silicon quantum dot molecule with tunable coupling, revealing detailed excitation spectra and energy level anticrossings, advancing silicon-based quantum computing prospects.

Contribution

It introduces a silicon double quantum dot with tunable tunnel coupling and detailed spectroscopic analysis, a step forward for silicon quantum computing.

Findings

Observation of excitation spectrum in weakly coupled dots

Detection of energy level anticrossing in strongly coupled dots

Demonstration of charge and energy quantization in silicon quantum dots

Abstract

We report electron transport measurements of a silicon double dot formed in multi-gated metal-oxide-semiconductor structures with a 15-nm-thick silicon-on-insulator layer. Tunable tunnel coupling enables us to observe an excitation spectrum in weakly coupled dots and an energy level anticrossing in strongly coupled ones. Such a quantum dot molecule with both charge and energy quantization provides the essential prerequisite for future implementation of silicon-based quantum computations.