Nonlocality and Entanglement via the Unruh effect

TL;DR

This paper explores how the Unruh effect influences quantum nonlocality and entanglement in accelerated qubits modeled as semiclassical detectors, revealing limits on violation of Bell and Svetlichny inequalities at high accelerations.

Contribution

It introduces a semiclassical detector model to analyze the Unruh effect's impact on nonlocality and entanglement, highlighting differences from free field models in non-inertial frames.

Findings

CHSH inequality cannot be violated at high acceleration.

Entanglement experiences sudden death at finite acceleration.

Svetlichny inequality cannot be violated at large acceleration.

Abstract

Modeling the qubit by a two-level semiclassical detector coupled to a massless scalar field, we investigate how the Unruh effect affects the nonlocality and entanglement of two-qubit and three-qubit states when one of the entangled qubits is accelerated. Two distinct differences with the results of free field model in non-inertial frames are (i) for the two-qubit state, the CHSH inequality can not be violated for sufficiently large but finite acceleration, furthermore, the concurrence will experience "sudden death"; and (ii) for the three-qubit state, not only the entanglement vanishes in the infinite acceleration limit, but also the Svetlichny inequality can not be violated in the case of large acceleration.