Recent advances in exciton based quantum information processing in quantum dot nanostructures

TL;DR

This paper reviews recent experimental progress in using excitons in quantum dot nanostructures for quantum information processing, focusing on single-qubit control and tunable two-qubit coupling.

Contribution

It presents new experimental insights into exciton coherence in single quantum dots and demonstrates voltage-tunable quantum coupling in quantum dot molecules.

Findings

Single quantum dot excitons exhibit coherent two-level system behavior.

Quantum dot molecules can be coupled coherently and tuned via external voltage.

Advances enable potential quantum information processing applications.

Abstract

Recent experimental developments in the field of semiconductor quantum dot spectroscopy will be discussed. First we report about single quantum dot exciton two-level systems and their coherent properties in terms of single qubit manipulations. In the second part we report on coherent quantum coupling in a prototype "two-qubit" system consisting of a vertically stacked pair of quantum dots. The interaction can be tuned in such quantum dot molecule devices using an applied voltage as external parameter.