Decoherence at the level of eigenstates

TL;DR

This paper extends the eigenstate decoherence hypothesis, suggesting that in large closed quantum systems, eigenstates exhibit classical-like properties locally, with rapid suppression of quantum coherence for small energy differences.

Contribution

The paper introduces an extension to the eigenstate decoherence hypothesis that accounts for rapid decoherence timescales in large quantum systems.

Findings

Eigenstates are locally classical-like in large systems.

Nondiagonal matrix elements are suppressed for small energy differences.

Decoherence occurs on extremely short timescales.

Abstract

An eigenstate decoherence hypothesis states that each individual eigenstate of a large closed system is locally classical-like. We extend this hypothesis to account for a typically extremely short time scale of decoherence. The extension implies that nondiagonal matrix elements of certain operators - quantumness witnesses - are suppressed as long as the energy difference between corresponding eigenstates is smaller than the inverse decoherence time.