Research On Improving The Fractional Delay Of Slow Light In The Thulium-doped Fiber

With the rapid development of the optical fiber communication technology. Now the research of slow light ha been hot topic. slow light in the optical fiber transmission have some significant advantage in a variety of technologies to realize slow light. This article mainly use the Coherent Population Oscillation to achieve transmission of slow light in the optical fiber, to establish the theoretical model and numerical simulation, discuss how to improve the relative time delay transmission of slow light in the thulium-doped optical fiber further. The relative time delay represents the ability of information storage in the medium. The article mainly include the following:The first chapter: introduce the slow light of research background and significance. At the same time, summarize several important technologies to realize slow light.The second chapter: this chapter mainly introduces the basic theory of phase velocity and group velocity of light and Kramers-Kronig dispersion relation.The third chapter: the chapter introduces the basic theory of coherent population oscillation, explain the two-level atomic system for steady-state response of monochromatic light field. And discuss absorption and refractive index of detecting light.The fourth chapter: Starting from the rate equation of Tm3+, combination with the transmission equation. Obtain the analytic expression of the ground state population,delayed signal light and the relative delay of the Tm3+. Meanwhile, the relative time delay of thulium-doped optical fiber to calculate base on numerical simulation. Discuss the relationship between oscillation of meta-stable particle number and the time delay under different length in thulium-doped optical fiber; Discuss the relationship between oscillation of metastable particle number and the time delay under different incident signal light power in thulium-doped optical fiber; Discuss the relationship between oscillation of metastable particle number and the time delay under different pump power in thulium-doped optical fiber; Discuss the relationship between oscillation of meta-stable particle number and the time delay under different dosage concentration in thulium-doped optical fiber. The chapter study on how to improve the relative time delay of slow light transmission in the thulium doped fiber. Through research and analysis: select high dosage concentration in thulium-doped optical fiber, longer optical fiber, large incident signal light power and appropriate pump power can receive time delay, at the same time enhance relative time delay. Discuss the relationship between best modulation frequency and every parameter.