Investigation On The Storage And Retrieval Of Surface Polaritons

In the past twenty years,the discovery of electromagnetical induced transparency(EIT)interests people greatly in nonliear optics based on quantum interference effect.The basic principle of EIT effect is to suppress greatly the absorption of optical field via a quantum interference effect between the transition pathways within atoms by an extra optical field.Except the suppression of the absorption of the optical field,EIT effect can dramatically change the dispersive of media and the propagation group velocity of optical field in the media.Additionally,making use of the EIT effect can enhance the nonlinear optical effect of media,which brings hope to realization of nonlinear optical process in single-photon level.These important properties of EIT effect not only exploits the weak-light level nonlinear optics research direction,but also have important practical application potential in areas such as all-optical control,quantum information processing,storage and retrieval of light.With the development of society and science and technology,the requirement of information processing technology becomes higher and higher.Storage and retrieval technology of light is possible to become the new age information storage technology,replacing the magnetic storage technology.One important application of the EIT effect is the storage and retrieval of light pules.Recently,Many science researchers around the world have investigated storage and retrieval of light based on EIT effect and obtain many outstanding achievements.But,nowadays,most of light storage systems we investigate are ultracold or free space atomic gases.Because of the high requirement of this system on technological means or the difficult realization in practical applications,many researchers develop industriously the storage and retrieval of light based on solid media at room temperature.The solid media not only avoids the problem of atomic gases diffusion,but also are easy to be controlled in practical applications.However,though the solid media have many advantages,they have low efficiency and fidelity of storage because of the weak EIT effect caused by the inhomogeneous broadening of energy levels.So,how to realize the stable propagation of lightpulses and the storage and retrieval of light with high efficiency and fidelity,is a very popular issue needed urgently to be solved.On the other hand,in recent years people have taken a great interest in surface plasmonic polaritons at the metal-dielectric interface.surface plasmonic polaritons have extensive application prospect in areas,like integrated optics,biosensor,all-optical quantum information processing,because of its energy localization.Recently,the interaction between surface plasmonic polaritons and quantum emitters doped at the dielectric-metal interface,has become an advanced issue.However,the losses of surface plasmonic polaritons in metal limit their applications.So,to realize long-range propagation of surface plasmonic polaritons is an important problem,which needs to be resolved immediately.The purpose of this thesis is to discuss the storage and retrieval of surface polaritons with high efficiency and fidelity,combined with advantages of surface plasmonic polaritons and EIT effect.On one hand,we can inject a pumping field to provide gain for surface polaritons based on EIT effect so that we can obtain the long-range propagation of surface polaritons.On the other hand,we can enhance the EIT effect in solid media by using the subwave length localization of surface polaritons,and realize the storage and retrieval of surface polaritons with high efficiency and fidelity.In this thesis,our work mainly focuss on the following two aspects:1.linear storage and retrieval of surface polaritons.We propose a scheme for the memory of surface polaritons via the EIT effect of quantum emitters with three-level configuration doped at the interface between a dielectric and a metamaterial.Based on the Maxwell-Bloch equations describing the interaction between light and quantum emitters,we derive the dispersion relationship of surface polariton.By using average field method,we show that,due to the strong mode confinement provided by the interface,the EIT effect can be largely enhanced.Furthermore,we demonstrate that the storage and retrieval of the surface polaritons can be realized by switching off and on of a control laser field by means of numerical simulation.Additionally,we show that the efficiency and fidelity of the surface polaritons memory can be improved much by using a weakmicrowave field,and we also give the corresponding theoretical explanation.The results we obtained are helpful for understanding of surface polariton properties and are hopeful of the promising applications in quantum and light information processing.2.The propagation properties and memory of surface polariton solitons with an optical pumping.We investigate the scheme of the realization and memory of surface polaritons with an external pumping field at the interface between a dielectric with four-level configuration quantum emitters doped and a metamaterial.By solving the Maxwell-Bloch equations of system,we can obtain the dispersion relationship of surface polaritons wiht gain.We also demonstrate that we can provide gain for our system by injecting an assisted pumping field,which can eliminate the Ohmic losses of surface polaritons in propagation process.What's more,by means of multi-scale method,we derive the nonlinear Schrodinger equation describing the evolution of surface polaritons.We study further the nonlinear property of surface polariton and demonstrate that we can realize the giant Kerr effect and obtain surface polariton solitons which can propagate steadily in this system.Finally,we show the realization of long-range surface polariton solitons and its high quality memory by means of numerical simulation.The results of this thesis not only are helpful for understanding of light storage with high efficiency and fidelity and the properties of surface polaritons,but also play a important guiding role theoretically on practical applications in areas such as quantum information processing and transmission,the weak-light level all-optical control and so on.