Entanglement dynamics of the two-spin system with time-dependent Heisenberg and Dzyaloshinskii-Moriya interactions

In the present paper, we study the entanglement dynamics of a two-spin system withHeisenberg interaction and Dzyaloshinskii-Moriya (DM) interaction. We assume thatboth interior interactions of the system are time-dependent. We consider two differentscenarios: In the first case, both Heisenberg and DM interactions are sinusoidal functions(sin (ωt)). The findings show that if the time-dependency of both interior interactions isthe same, the quantum entanglement of the system presents more robustness and itstemporal fluctuations reduce significantly over time. In the second case, DM interactionis considered as D ∝ cos (ωt). The findings imply that this kind of time-dependencycauses the strong fluctuations of the entanglement, so that sometimes the correlationreaches zero. Therefore, in order to achieve a more stable entanglement over time, it isbetter that the time dependency of the Heisenberg interaction and DM interaction wouldbe the same.