Storage and Retrieval of Surface Polaritons

Abstract

We investigate the memory of surface polariton (SP) via the electromagnetically induced transparency (EIT) of quantum emitters doped at the interface between a dielectric and a metamaterial. We show that, due to the strong mode confinement provided by the interface, the EIT effect can be largely enhanced; furthermore, the storage and retrieval of the SP can be realized by switching off and on of a control laser field; additionally, the efficiency and fidelity of the SP memory can be improved much by using a weak microwave field. The results reported here are helpful not only for enhancing the understanding of SP property but also for promising applications in quantum information processing and transmission.KEYWORDS: electromagnetically induced transparency, surface polaritons, light storage In past two decades, considerable attention has been paid to the research on electromagnetically induced transparency (EIT), a typical quantum interference effect occurring in resonant three-level atomic gases. The light behavior in EIT systems possesses many striking features, including substantial suppression of optical absorption, significant slowdown of group velocity, excellent coherent control of the interaction between light and atoms at weak light level, and so on. 1One of important applications of EIT is light storage, which has important applications in quantum informatics. 2 The basic mechanism of EIT-based light storage is that the system allows a stable combined excitation (called dark-state polariton 3 ) contributed by atomic coherence together with a probe (or called signal) laser field, which displays an atomic character when a control laser field is switched off and a photonic character when the control field is switched on. The storage of probe optical pulses based on atomic EIT has been verified in many experiments. 4,5 Recently, the possibility of weak-light soliton memory in a cold atomic gas has also been suggested. 6Up to now most of works on EIT-based light storage were carried out in free atomic gases.Although there are some advantages (e.g., long coherence time), such EIT and light storage scheme require special and cumbersome conditions, such as large device size, which hamper compact chip-integrated applications. In contrast, solid media is on demand for practical applications because they are easy for device integration. Some materials (like quantum dots or dopant ions in solids) can combine advantages of atomic gases and solids to get long coherence time and large optical density. Thus the realization of the light storage based on such hybrid materials are more desirable comparing with the atomic gases in free space. 7,8 In recent years, much effort has been focused on the study of surface polaritons (SPs), i.e., polarized electromagnetic waves propagating along a metal-dielectric interface with the wave coupled to charge density oscillations. 9 SPs produced in metal-dielectric interfaces doped with quantum emitters have also been considered in many studies. [10][11][12][13][14][15][16][17][18][19...