Theoretical Details And Experiments Of A Ring Laser With Two Wavelengths And Tunable Based On Semiconductor Optical Amplifier

Dual-wavelength laser based on semiconductor optical amplifier(SOA) can provide two channel signal light source at the same time. It also has the advantages of good beam quality, narrow line width, simple and compact structure so that has a broad application prospect in all optical communication, sensing, terahertz optical signal processing and wireless communications, and so on. A stable dual-wavelength ring laser using semiconductor optical amplifier as an inhomogeneous gain medium and FP-Laser as both an inhomogeneous gain medium and an actively mode-locking element is proposed and demonstrated experimentally. The main contents are as follows:At the first of this paper, the background and the research progress of the fiber ring laser based on SOA all over the world have been introduced, and give the brief of optical amplifier. Second, theoretical details of the multiple wavelength optical fiber ring laser based on SOA have also been presented, such as the operation principle of external cavity semiconductor laser and actively mode-locked mechanism. Then, numerical simulation of the gain modulation characteristics of the Semiconductor Optical Amplifier(SOA) has been performed, using the segmented model which including the rate equation for the carrier density and the simplified propagation equation for the electric field. The numerical simulation results have been experimental confirmed using pump and probe experiments. Finally, a stable dual-wavelength semiconductor fiber ring laser is proposed and demonstrated experimentally. Detailed analyses and quantitative calculation of the Pulse-width, and the operation principles of the mode-locked lasing with two wavelengths have also been presented.The above results can provide an instructive insight to obtain ultra-short optical pulse with high repetition rates, high peak power and large wavelength tunable range.