Quantum theory of spectral diffusion induced electron spin decoherence

TL;DR

This paper introduces a quantum cluster expansion method to explain electron spin decoherence caused by nuclear spin fluctuations, aligning well with experimental data without relying on phenomenological assumptions.

Contribution

It develops a microscopic quantum approach for spectral diffusion, providing a fundamental explanation for electron spin decoherence phenomena.

Findings

The method accurately reproduces Lorentzian diffusion of Hahn echoes.

Numerical results match recent experiments in phosphorus doped silicon.

The approach avoids phenomenological Markovian assumptions.

Abstract

A quantum cluster expansion method is developed for the problem of localized electron spin decoherence due to dipolar fluctuations of lattice nuclear spins. At the lowest order it provides a microscopic explanation for the Lorentzian diffusion of Hahn echoes without resorting to any phenomenological Markovian assumption. Our numerical results show remarkable agreement with recent electron spin echo experiments in phosphorus doped silicon.