Bell inequality violation versus entanglement in presence of local decoherence

TL;DR

This paper investigates how local decoherence affects entanglement and Bell inequality violations in two qubits, revealing that entanglement persists longer than Bell violations under experimental conditions with superconducting qubits.

Contribution

It provides a detailed analysis of decoherence effects on entanglement and Bell violations, incorporating realistic Kraus operators at arbitrary temperatures.

Findings

Entanglement survives longer than Bell violations under local decoherence.

Decoherence modeled with Kraus operators for dephasing and relaxation.

Implications for experiments with superconducting phase qubits.

Abstract

We analyze the effect of local decoherence of two qubits on their entanglement and the Bell inequality violation. Decoherence is described by Kraus operators, which take into account dephasing and energy relaxation at an arbitrary temperature. We show that in the experiments with superconducting phase qubits the survival time for entanglement should be much longer than for the Bell inequality violation.