Coherence and entanglement dynamics of vibrating qubits

TL;DR

This paper studies how vibrational motion in trapped ion qubits affects their coherence and entanglement, revealing that vibration can prolong coherence but accelerate entanglement decay, with implications for quantum resource management.

Contribution

It demonstrates the dual effect of qubit vibrations on coherence preservation and entanglement decay, offering new insights into quantum resource dynamics in moving qubits.

Findings

Vibration prolongs initial coherence in single and two-qubit systems.

Vibration accelerates entanglement decay between qubits.

Photon-phonon correlation dynamics are highly dependent on initial qubit states.

Abstract

We investigate the dynamics of coherence and entanglement of vibrating qubits. Firstly, we consider a single trapped ion qubit inside a perfect cavity and successively we use it to construct a bipartite system made of two of such subsystems, taken identical and noninteracting. As a general result, we find that qubit vibration can lead to prolonging initial coherence in both single-qubit and two-qubit system. However, despite of this coherence preservation, we show that the decay of the entanglement between the two qubits is sped up by the vibrational motion of the qubits. Furthermore, we highlight how the dynamics of photon-phonon correlations between cavity mode and vibrational mode, which may serve as a further useful resource stored in the single-qubit system, is strongly affected by the initial state of the qubit. These results provide new insights about the ability of systems made of moving qubits in maintaining quantum resources compared to systems of stationary qubits.