Signatures of chaos in the dynamics of quantum discord

TL;DR

This paper demonstrates how quantum discord dynamics reveal signatures of chaos in a multiqubit system modeled as a quantum kicked top, showing quasiperiodic behavior in regular regions and loss of it in chaotic regions.

Contribution

It provides the first evidence of chaos signatures in the dynamics of quantum discord, linking quantum correlations to classical chaos structures.

Findings

Discord dynamics are quasiperiodic in regular regions.

Loss of quasiperiodicity in chaotic regions.

Opposite behavior observed between discord and entanglement.

Abstract

We identify signatures of chaos in the dynamics of discord in a multiqubit system collectively modelled as a quantum kicked top. The evolution of discord between any two qubits is quasiperiodic in regular regions, while in chaotic regions, the quasiperiodicity is lost. As the initial wave function is varied from the regular regions to the chaotic sea, a contour plot of the time averaged discord remarkably reproduces the structures of the classical stroboscopic map. We also find surprisingly opposite behaviour of two-qubit discord versus two-qubit entanglement. Our calculations provide the first evidence of signatures of chaos in dynamically generated discord.