Suppressing Fast Dipolar Noise in Solid-State Spin Qubits

TL;DR

This paper introduces Hybrid-LG, a new decoupling method that effectively suppresses fast dipolar noise in solid-state spin qubits, significantly extending their coherence times without extra control power.

Contribution

The paper presents Hybrid-LG, a novel decoupling mechanism that suppresses intra-bath dipolar interactions, improving spin coherence in NV centers in diamond.

Findings

At least twofold increase in NV center coherence time.

Effective suppression of intra-bath dipolar interactions.

No additional control power needed for enhancement.

Abstract

Spin qubit coherence is a fundamental resource for the realization of quantum technologies. For solid-state platforms, spin decoherence is dominated by the magneto-active environment in the lattice, limiting their applicability. While standard dynamical decoupling techniques, such as the Hahn echo, extend central spin coherence, they fail to suppress the fast noise arising from strong dipolar interactions within the bath. Here, we present a decoupling mechanism, Hybrid-LG, that suppresses intra-bath dipolar interactions -- thus, fast noise acting on spin qubits- and demonstrate its effectiveness in extending spin coherence through efficient in-house CCE simulations. Specifically, we investigate one of the most widely exploited solid-state quantum platforms: an ensemble of nitrogen-vacancy (NV) centers in diamond coupled to a large and dense bath of substitutional nitrogen paramagnetic impurities (P1 centers). Our results reveal at least a twofold enhancement in NV coherence time relative to standard techniques including P1 center driving, without requiring additional control power.