Spin decay and quantum parallelism

TL;DR

This paper investigates how a single spin's decoherence depends on the initial state of its nuclear environment, highlighting the roles of quantum parallelism and entanglement in the process.

Contribution

It demonstrates the contrasting decoherence behaviors arising from different initial nuclear spin states, emphasizing the impact of quantum correlations.

Findings

Product states lead to different decoherence dynamics than correlated states.

Randomly correlated states exemplify quantum parallelism and entanglement effects.

Initial state significantly influences spin decoherence behavior.

Abstract

We study the time evolution of a single spin coupled inhomogeneously to a spin environment. Such a system is realized by a single electron spin bound in a semiconductor nanostructure and interacting with surrounding nuclear spins. We find striking dependencies on the type of the initial state of the nuclear spin system. Simple product states show a profoundly different behavior than randomly correlated states whose time evolution provides an illustrative example of quantum parallelism and entanglement in a decoherence phenomenon.