Extending Qubit Coherence Time via Hybrid Dynamical Decoupling

TL;DR

This paper introduces a hybrid dynamical decoupling method combining pulsed DD and bath spin polarization to significantly extend qubit coherence times, advancing quantum information processing capabilities.

Contribution

It presents a novel hybrid approach that integrates pulsed DD with bath spin polarization, achieving 2-3 orders of magnitude coherence time enhancement in the central spin model.

Findings

Coherence time extended by 2-3 orders of magnitude.

Hybrid DD outperforms traditional methods in coherence preservation.

Applicable to various quantum systems like GaAs and silicon.

Abstract

Dynamical decoupling (DD) and bath engineering are two parallel techniques employed to mitigate qubit decoherence resulting from their unavoidable coupling to the environment. Here, we present a hybrid DD approach that integrates pulsed DD with bath spin polarization to enhance qubit coherence within the central spin model. This model, which can be realized using GaAs semiconductor quantum dots or analogous quantum simulators, demonstrates a significant extension of the central spin's coherence time by approximately 2 to 3 orders of magnitude that compared with the free-induced decay time, where the dominant contribution from DD and a moderate improvement from spin-bath polarization. This study, which integrates uniaxial dynamical decoupling and auxiliary bath-spin engineering, paves the way for prolonging coherence times in various practical quantum systems, including GaAs/AlGaAs, silicon and Si/SiGe. And this advancement holds substantial promise for applications in quantum information processing.