Decay of nonlocality due to adiabatic and quantum noise in the solid state

TL;DR

This paper investigates how different types of noise in solid-state Josephson qubits cause the decay of quantum nonlocality, highlighting qualitative differences and comparing nonlocal correlations with entanglement dynamics.

Contribution

It provides a detailed analysis of how adiabatic and quantum noise uniquely affect nonlocality decay in Josephson qubits, with quantitative results relevant to practical systems.

Findings

Adiabatic noise mainly causes gradual decay of nonlocality.

Quantum noise leads to more abrupt loss of nonlocal correlations.

Nonlocality and entanglement decay dynamics differ significantly.

Abstract

We study the decay of quantum nonlocality, identified by the violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality, for two noninteracting Josephson qubits subject to independent baths with broadband spectra typical of solid state nanodevices. The bath noise can be separated in an adiabatic (low-frequency) and in a quantum (high-frequency) part. We point out the qualitative different effects on quantum nonlocal correlations induced by adiabatic and quantum noise. A quantitaive analysis is performed for typical noise figures in Josephson systems. Finally we compare, for this system, the dynamics of nonlocal correlations and of entanglement.