Influence of an external electromagnetic field on quantum entanglement and coherence in a two-qubit graphene system

Abstract Graphene, with its two-dimensional carbon structure, exhibits unique quantum properties that are crucial for quantum computing. In this paper, we investigate the influence of an external electromagnetic field on quantum coherence and entanglement between two qubits in graphene lattices. Our findings show that an electromagnetic field with high field strength ($\xi_{0} \sim 50$ meV$^2$) and low frequency ($\omega =0.117 \, \mathrm{eV}$) significantly enhances quantum entanglement and coherence, even at elevated temperatures ($T \sim 20$ meV). By adjusting the frequency and the field strength, these quantum effects can be preserved long enough at high temperatures. Furthermore, circular polarization of the electromagnetic field is found to be more effective than linear and elliptical polarizations in optimizing these effects. These results highlight the critical role of electromagnetic fields in enhancing quantum properties, potentially paving the way for advancements in quantum computing and related technologies.