Decoherence in the Spin Bath

TL;DR

This paper presents a mathematical framework for understanding decoherence caused by spin baths, highlighting differences from oscillator baths and implications for quantum measurement theory.

Contribution

It introduces a novel description of decoherence in spin baths, emphasizing their non-dissipative nature and broad relevance to quantum systems.

Findings

Decoherence in spin baths can occur without dissipation.

Spin baths influence quantum measurement differently than oscillator baths.

Results have implications for quantum information processing.

Abstract

We develop a mathematical description of the decoherence caused by "spin baths", such as nuclear spins or magnetic impurities. In contrast to the usual oscillator bath models of quantum environments, decoherence in the spin bath can occur without any dissipation. Given the almost ubiquitous presence of nuclear spins in nature, our results have important consequences for quantum measurement theory, particularly as the decoherence mechanisms in spin baths work very differently from those in oscillator baths.