| With the rapid development of microelectronics technology,optoelectronics technology, Computer and communication technology, humansociety is entering into an information era. Information society is nowsupported by the global-wide information high way and the optical fibercommunication system is a key part of the global-wide information high way.Optical amplifier is a necessary apparatus of the new generation optical fibercommunication. Optical amplifier technology promotes the development ofoptical fiber communication in a big sense. It plays a role of milestone inpractice. It resolved the distance restriction of optical transmission network(OTN) which is given by attenuation.. It amplifies optical signal in a real-time,on-line, band-wide, high-gain, low-noise and low power-wasting way,meanwhile it amplifies optical signal in a transparent way for wavelength,velocity and modulation means. It makes all that wavelength divisionmultiplexer (WDM), dense wavelength division multiplexer (DWDM), fulloptical transmission,optical soliton transmission which is characterized bysuper high speed, super capacity and super long-way to become the truth.Erbium doped optical waveguide amplifier(EDWA) is another new kind ofoptical amplifier followed the Semiconductor optical amplifier (SOA) andErbium doped fiber amplifier (EDFA). These years research about EDWA isbecoming a hotspot in the region of optical fiber communication andphotoelectron. At the same time, circuit of optical communication consisted ofseparate components and in planar light-wave circuits (PLC), all kinds ofoptical components have losses. It urgently needs a new kind of amplifierwhich is in low price and can be integrated easily. EDWA is an optimizedselection for an appropriate gain. Among all the materials which are used inthe integration optics, polymer material has some merits that is high rare-earthions doped concentration, easy control of the refractive index, relatively highelectric-optic coupling coefficient, relatively low dielectric constant,shortresponse time,low thermal losses,small birefringence, easy fabrication,cost-effectiveness and so on, compare with the traditional inorganic materials.For the reasons enumerated above, polymeric optical waveguide amplifier isbecoming a research focus.Erbium doped polymeric optical waveguide amplifier is doped Er3+ inpolymer material, we make use of photoresist and aluminum film as mask inO2 reactive ion etching technology etch waveguide in polymer material ofsilicon substrate, and is excited by the 980nm pump laser, output the amplified1535nm optical signal. In this thesis we study the Erbium doped polymericoptical waveguide amplifier. The main content is listed as follows:1.Summarize the main technology in the EDWA research region.Generalize the developing process and achievement in recent years about fiberoptical communication and EDWA. Meanwhile talk about the characteristicand foreground of EDWA.2.We analyzed the theory of optical waveguide amplifier, by analyzingthe energy level structure of Er3+, we explained the theory of opticalwaveguide amplifier output the optical signal. By analyzing the influence tothe gain characteristic of optical waveguide amplifier given by wave-guidelength, the thickness of Erbium ion, cooperative upconversion affection and soon, we get some useful results: (1)Excited state absorbtion restrict the highestpump power of EDWA, so there is a saturated pump power to make theamplifier of single side pump to have the biggest length. (2)For Erbium dopedwaveguide amplifier, there is an optimized packaging density, neither highernor lower concentration are good for the amplifier. (3)The cooperativeupconversion affection engendered by high packaging density will debase theplus and results in the deterioration of the plus and noise parameter. For thegoal of both high concentration of Er3+ and low upconversion affection, wecan take the approach of Er3+-Yb3+ codoped (EYCDWA), making use of theenergy transfered by Er3+ and Yb3 to minish the cluster of Er3+ . These resultsplay an instructional role in the logical selection of materials of opticalwaveguide amplifier and optimize the structure design.3. We proposed a photoresist and aluminum film as mask in O2 reactiveion etching technology which is used for polymer waveguide device, at thesame time we make a experimental research for Erbium doped polymer opticalwaveguide amplifier. According to the requirement of polymeric opticalwaveguide amplifier, we selected the poly-methyl-methacrylate–co-glyciclylmethacrylate material which is adulterated bydibenzoylmethide-methyl-methacrylate with Erbium. Analysed the chemistrystructure expression and test the performance of the material, we usedellipsometry to measure the film-formed characteristic and refractive index ofthe material, the results show that refractive index of material decreasedgradually as the wavelength increasing. The refractive index is 1.5048 whenwavelength is 1.55μm;The peak value wavelength of the materialphotoluminescence spectrum is nearly 1550nm, spectral width is 80nm, that isto say this material can be made of waveguide amplifier which is used foroptical communication and its bandwidth advantage is very well.We made a systemic research for the influence of the device whensplashing plating-aluminium and vaporizing plating-aluminium and giveapplying range of each other. We discuss the influence of etching rate andcrude degree in detail when using different parameters. Finally, wesummarized the technical flow of fabricating polymeric optical waveguideamplifier.4. We designed and develop the optical waveguide amplifiercharacteristic measurement system, tested characteristic of optical waveguideamplifier. The system is based on the technique of wimble's fiber waveguidecoupling, coupling efficiency is 92.3%, the amplifier multiple of the systeminfrared vidicon is large and can be accommodated, we can accommodate thenicety position of fiber and waveguide section easily base on the clear image,solved the large coupling losses in other measured system in a better way.Lower the connection losses by taking the method of coupler, isolator andlaser's tail fiber direct fusion. We make use of this system to measure theEDWA device's spontaneous radiation spectrum, system losses, the connectionbetween inner gain and wavelength of signal, power and pump power. Theresults show that spontaneous radiation spectrum's peak value wavelengthwould move when pump power is changing, photoluminescence power islarger when the pump power increase;System losses is the largest at thewavelength of 1535.2nm.When the input power is 150mw , at the range of1520-1580nm, the approximately losses of the system is 8dB. The pulsing ofthe pump power can compensate the system losses. When the input signal islow, the gain is increasing when the pump power is larger, but increase is notliner, and saturation gradually. There is a threshold value pump power. Whenthe pump power is the same, large signal gain is less then the low signal gain,amplify gain is increasing when the pump power increase. However, thethreshold value pump power, make the gain saturate gradually. There is aconsistence between the experiment result and academic analyses. |
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