Doped Doped Waveguide Amplifier Gain Flattening Filter

With the development of communication, the technology of optical amplifier develops quickly in recent year. Er3+-doped optical waveguide amplifier (EDWA) become the hotspot of study because of its advantage like small volume, high gain etc. With the bandwidth of communication is expanded on and on, the gain bandwidth of EDWA is expected to expand correspondingly. The gain spectrum in 1531~1565nm of traditional EDWA is not flatness and cannot accord with the need of DWDM or the other optical communication way out and away. So the technology of gain flatting of EDWA is come forth. Based on the model of two-way's EDWA, a way using complete medium optical thin film filter deposited on the EDWA output surface to realize the gain flatting is put forward in this paper. The filter can integrate in the same underlay with the single EDWA like lamp-house to bump and modulator etc, so the way is easier to integrate, miniaturization and stronger applicability compare with the tradition gain flatting approach.In the paper, filter of EDWA for gain flatting is expounded from design of coating system, technics of monitor and the produce or testing of sample. In the aspect design coating system, a new idea to combine the general way and the simulated annealing genetic algorithms (SAGA) is brought forward .SAGA is applied in the design of coating system, whole and local search are considered. Then the way and the process of SAGA applied in design is expounded. In this paper, a new way to monitoring non-ordinary coating system is expounded. The wavelengths can be got by approach of numerical search. Then the theory and the way to monitor using the approach is expounded, the error is analyzed.. In this paper, coating system is optimized, then the good result is realized theoretically: wavelength 1548~1566nm, the value of gain flatting is ; Wavelength in 1537~1548nm, the value is; The value in 1531~1536nm is; On the whole range of wavelength(1631~1566nm), the gain is up . Gain of wavelength 1531nm~1549nm is flatted in the last experimentation, the value of gain flatting is