  We explore the interplay between acceleration radiation and the dynamical
Casimir effect (DCE) in the field of superconducting quantum technologies,
analyzing the generation of entanglement between two qubits by means of the DCE
in several states of qubit motion. We show that the correlated absorption and
emission of photons is crucial for entanglement, which in some cases can be
linked to the notion of simultaneity in special relativity.
