Robustness of Charge-Qubit Cluster States to Double Quantum Point Contact Measurement

TL;DR

This paper studies how charge-qubit cluster states in quantum dot systems withstand measurement-induced disturbances, revealing that dynamical fluctuations from double quantum point contact measurement impact the states more than static fluctuations.

Contribution

It introduces a model for trap states as dynamical fluctuations in DQPC and compares their effects to static fluctuations on cluster state robustness.

Findings

Dynamical fluctuations significantly degrade cluster state fidelity.

Static fluctuations have a lesser impact on robustness.

Dynamical effects are more critical in measurement-induced decoherence.

Abstract

We theoretically investigate the robustness of cluster states in charge qubit system based on quantum dot (QD) and double quantum point contact (DQPC). Trap state is modeled by an island structure in DQPC and represents a dynamical fluctuation. We found that the dynamical fluctuations affect the cluster states more than static fluctuation caused by QD size fluctuation.