Decoherence induced by anisotropic hyperfine interaction in Si spin qubits

TL;DR

This paper investigates how anisotropic hyperfine interactions cause decoherence in silicon-based phosphorus donor electron spins, offering insights into minimizing decoherence and achieving a comprehensive understanding of the underlying mechanisms.

Contribution

It provides a detailed analysis of anisotropic hyperfine-induced decoherence in Si:P qubits and proposes strategies to reduce this decoherence by magnetic field orientation.

Findings

Resonance-like contributions from nuclear spins affect decoherence.

Orienting magnetic fields can minimize hyperfine-induced decoherence.

The model aligns well with experimental data.

Abstract

We study Si:P donor electron spin decoherence due to anisotropic hyperfine (AHF) interaction with the surrounding nuclear spin bath. In particular, we clarify the electron spin echo envelope modulation (ESEEM) in the Si:P system and the resonancelike contributions from nuclear spins in various shells away from the P atoms. We suggest an approach to minimize AHF-induced decoherence by avoiding the resonances and orienting an applied magnetic field along directions that can periodically eliminate contributions from the dominant nearest neighbor atoms. Our remarkable agreement with experiment demonstrates nearly complete understanding of electron spin decoherence in Si:P when combining ESEEM, spectral diffusion, instantaneous diffusion, and spin-lattice relaxation.