The potential application of slow light in optical buffer and optical data storage,certainly will bring a lagre progress to communication.Because of the particular advantages of CPO in controlling the speed of light,it attracts considerable attentions.Here gives the principle of CPO technology to control light velocity,and discusses its research progress.
The potential application of slow light in optical buffer and optical data storage,certainly will bring a lagre progress to communication.Because of the particular advantages of CPO in controlling the speed of light,it attracts considerable attentions.Here gives the principle of CPO technology to control light velocity,and discusses its research progress.
Starting with a concise historical introduction to EIT,CPO and SBS methods,this article gives a comprehensive review to the advances in the research of controllable fast and slow light,with the emphasis on the history,physical principle,and experiments of slow light via coherent population oscillation approach,which is effective in the realization of ultraslow light at the room temperature.The article also discusses the problems and difficulties existing in the application of controllable fast and slow light.
In this paper, we proposed a novel approach to demonstrate optically controllable pulse group velocity at telecommunication wavelengths in EDF due to CPO. First we reviewed recent advances in slow-light-based optical signal processing, then we study slow and fast light propagation in erbium doped fiber abstractly based on theory and simulation model. It is revealed though the research that the time delay and advancement depends greatly on the pump power, influence of the ion density on the group velocity of light propagation is also studied. Based on our discussion, the optimization parameters should be selected in order to obtain more appropriate time delay and the slowdown of group velocity, which is of great importance to the communication industry.
The last decade is of great significance for the development of slow light technology.In order to study on the slow light technology deeply,several kinds of slowing light technologies,such as Electromagnetically Induced Transparency(EIT),Coherent Population Oscillation(CPO),Stimulated Brillouin Scattering(SBS) and photonic crystal waveguide,were contrasted and analyzed.Also some important theoretical and technical developments to improve performance of slow light in last decade were introduced,and then problems and shortcomings existing in slowing technology were discussed.Finally,this paper focuses on some novel technologies of slowing down light velocity and their primary applications.Moreover,it forecasts the future developing trends of slow light and its potential applications.Through research on slow light,results show that slow light will realize more and more significant application values in the field of optical fiber sensing and other fields.
The technology of optically controlled delay of light in optical fibers is attracting so much attention recently in view of its flexibility,easy operation and ability to accelerate the development of the modern optical communication.In this paper,we review the research progress of time delay controlled by light in fibers.The basic principle of optically controlled velocity of light is introduced.Several new technologies of time delay via nonlinear effects in optical fiber are emphatically described,such as Stimulated Brillouin Scattering, Stimulated Raman Scattering,Optical Parametric Amplifier,Wavelength Conversion,Soliton Collisions,Coherent Population Oscillation etc,and analyzed the advantage and disadvantage of each method.Finally,the significance and development prospect of this research are discussed.
The ability to manipulate the speed of light has recently become one of the most exciting emergent topics in optics. There are several experimental demonstrations showing the capability to slow down light more than six orders of magnitude in a variety of media, ranging from atomic vapor, solid state crystal, to semiconductors. These results have led to intensive research into new materials, devices, and system studies that examine their impact to new applications. It is believed that we are on the verge of a dramatic change in the way we envision and construct communication, processing and control systems. One direct application of slow and fast light devices is in the area of communications. One grand challenge remaining in information technology today is to store and buffer optical signals directly in optical format. As such, optical signals must be converted to electronic signals to route, switch, or be processed. This resulted in significant latencies and traffic congestions in current networks. In addition, keeping the data in optical domain during the routing process can greatly reduce the power, complexity and size of the routers. To this end, a controllable optical delay line can effectively function as an optical buffer, and the storage is proportional to the variability of the group velocity. In addition to optical buffers, slow and fast light devices can be used as tunable true-time delay elements in microwave photonics, which are important for remotely controlling phased array antenna. Other novel applications include nonlinear optics, optical signal processing, and quantum information processing. There are various approaches that can be used to vary the optical group velocity. Ultraslow or fast group velocity may result from a large material dispersion, waveguide dispersion, or both. In this paper, the authors provide a review of recent progress of slow and fast light using semiconductor devices. Specifically, they will discuss results obtained using semiconductor quantum-well/quantum-dot absorber and optical amplifiers. Slow and fast light are controllable electrically by changing the bias current or voltage as well as optically by changing the pump laser intensity and wavelength. Delay-bandwidth tradeoff and other figures of merits are analyzed
Fast or slow light propagation means that the group velocity of a quasi-monochromatic light pulse propagating in a resonant medium can be significantly faster or slower than the light speed in a vacuum. Since the end of the last century and the beginning of this century, studies on this subject have attracted a great deal of interest. Remarkable progress has been achieved, based on various nonlinear optical interactions in resonant media. The fundamental research on this subject can enrich our understanding of special relativity and causality in physics. On the other hand, those mechanisms and techniques developed for fast and slow light propagation have provided the potential for many future applications, such as optical buffers and variable delay lines for optical networks, optical computing, optical telecommunications, optical data storage, and signal processing.