Design And Implementation Of All-optical Wavelength Conversion Switch Based On Micro-structure Fiber Sagnac Loop

All-optical information processing technology has played a key role indeveloping the high-speed optical communication networks. In recentyears, all-optical switching has increasingly drawn broader attention, andis the most important appliance in the all-optical information process. Theall-optical switching uses the light to control the light directly in theoptical domain, i.e., without the light-to-electricity and electricity-to-lightswitch, is the most important optical passive device of the all-opticalnetworks in the future.This thesis, based on a broad research on the literature, gives a briefintroduction on all-optical logic devices with different non-linear devicesas components, and further invents an all-optical wavelength conversionswitching based on photonic crystal fiber (PCF). The experiemtal systemuses femtosecond laser as pump source, and uses tunable laser as its signalsource. After being amplified by EDFA, the two beams of light areinjected into Sagnac loop which is made by coupler with splitting ratio of5:5. The Sagnac loop is made by a10m PCF fiber with its non-linearparameter equals to~11(Wkm)-1. When we use the oscilloscope andoptical spectrum analyzer to dectect the signal from the output port of Sagnac loop, four-wave mixing phenomenon can be obersevered, and alsoin the time domain we can observe idle frequency light with samefrequency as pump light, which realizes the high speed all-opticalwavelength conversion switching. Addtionally, by adjusting thewavelengths of signal light or pump light, one can make the wavelength ofidler light change in a big scope. The adjusting range of wavelength ofall-optical wavelength conversion switch covers C and L band.Besieds, this thesis also studies the side coupling effect of twoparallelly and closely placed microfiber. In simulation, when keeping thetwo fibers’ distance fixed and the fiber’s diameter variable, the energyalternate cycle length of the fiber increases as the diameter increase. Whenkeeping the fiber’s diameter fixed and the distance variable, the energyalternating cycle length of the fiber increases as the distance increases.When keeping all the other parameters fixed, the energy alternating cyclelength of the fiber increases as the conical degree of the fiber increases.Then, we make the Sagnac loop using the microfiber according to thesimulation results of the microfiber’s side coupling process, after whichon-line measuring methods are provided. Finally, we propose a viablesolution to make the all-optical wavelength conversion switching viamicrofiber Sagnac loop and control fiber.