Fiber Laser Based On Semiconductor Optical Amplifier

The fiber laser based on semiconductor optical amplifier has some advantages,such as simple structure,stable performance and low cost.It has wide applications in optical fiber communication systems,laser technology,spectroscopy,bio-photonics,optical information processing,and so on.The key problems in the fiber laser based on semiconductor optical amplifier are studied in this dissertation,the main research contents are as following:1.The spontaneous emission characteristic of InP/InGaAsP multi-quantum wells is studied by using the classical theory about the interaction between radiation and matter,and the experience formula of the line-shape function describing spontaneous emission with fitting method.The results show that the line-shape function describing spontaneous emission of InP/InGaAsP multi-quantum wells is a Gaussian distribution function,and the InP/InGaAsP multi-quantum wells semiconductor material belongs to inhomogeneous broadening laser material at room temperature.2.A novel single-wavelength fiber laser based on a semiconductor optical amplifier is proposed and experimentally studied,a stable single-wavelength laser output is obtained with a fiber Bragg grating as wavelength selector.It's demonstrated that a lasing at 1550.2nm with 0.144 nm of 3dB bandwidth and 35 dB of signal-to-noise ratio with the 200 mA of injection current of semiconductor optical amplifier and 25? of operating temperature of the fiber Bragg grating.The central wavelength of laser is a function of the operating temperature of fiber Bragg grating,its temperature coefficient is 0.01512nm/?.3.A novel dual-wavelength fiber laser based on a semiconductor optical amplifier is proposed and experimentally studied,a stable dual-wavelength lasing is obtained with two cascaded fiber Bragg gratings as wavelength selectors.It's demonstrated that a dual-wavelength lasing at 1550.072 nm and 1550.624 nm with-37.43 dBm and-44.77 dBm of output power and 35 dB and 27 dB of the signal-to-noise ratio,the wavelength spacing is 0.552 nm,and wavelength spacing is a function of the operating temperature difference of the two cascaded fiber Bragg grating.4.A novel dual-wavelength fiber laser based on a semiconductor optical amplifier with external DFB laser injection is proposed and experimentally studied,a stable dual-wavelength lasing is obtained with an external DFB laser and a fiber Bragg grating as wavelength selectors.In this case,one of the lasing wavelengths is locked by the external DFB laser,and the other is selected by the fiber Bragg grating.It's demonstrated that a dual-wavelength lasing at 1550.06 nm and 1553.88 nm with the wavelength spacing of 3.82 nm.Compared with the case using two cascaded fiber Bragg gratings as wavelength selectors,this solution can obtain larger wavelength spacing.5.A novel multi-wavelength fiber laser based on a semiconductor optical amplifier is proposed and experimentally studied,a stable multi-wavelength lasing is observed.The effect of the pump injection current of the semiconductor optical amplifier on the wavelength number of lasing is explored.The results show that the lasing wavelength number can be changed by adjusting the pump injection current of the semiconductor optical amplifier,the lasing wavelength number is proportional to pump injection current,but the saturable value of the lasing wavelength number exists.