Dipole–dipole interactions enhance non-Markovianity and protect information against dissipation

Preserving non-Markovianity and quantum entanglement from decoherence effect is of theoretical and practical significance in the quantum information processing technologies.In this context, we study a system S that is initially correlated with an ancilla A, which interacts with the environment E via an amplitude damping channel.We also consider dipole-dipole interactions(DDIs) between the system and ancilla, which are responsible for strong correlations.We investigate the impact of DDIs and detuning on the non-Markovianity and information exchange in different environments.We show that DDIs are not only better than detuning at protecting the information(without destroying the memory effect) but also induce memory by causing a transition from Markovian to non-Markovian dynamics.In contrast, although detuning also protects the information, it causes a transition from non-Markovian to the Markovian dynamics.In addition, we demonstrate that the non-Markovianity grows with increasing DDI strength and diminishes with increasing detuning.We also show that the effects of negative detuning and DDIs can cancel out each other, causing a certain loss of coherence and information.

High-dimensional atomic microscopy in surface plasmon polaritons

We develop a new scheme of two-dimensional(2D)and three-dimensional(3D)atom localization via absorption and gain spectra of surface plasmon polaritons(SPPs)in a closed loop four-level atomic system.For the atom–field interaction,we construct a spatially dependent field by superimposing two(three)standing-wave fields(SWFs)in 2D(3D)atom localization,respectively.We achieve high-precision and high spatial resolution of an atom localization by appropriately adjusting the system parameters such as probe field detuning and phase shifts of the SWFs.The absorption and gain spectra are used to attain information about the position of an atom in SPPs.Our proposed scheme opens up a fascinating way to improve the atom localization that supplies some practical applications in a high-dimensional SPPs.