Control Of The Tunable Fiber Ring Laser Based On Semiconductor Optical Amplifier

The Tunable Fiber Ring Laser based on semiconductor optical amplifier is connected by optical fiber, SOA and tunable filter, couplers, isolators, etc, which has high tuning speed, the narrow output spectral line width, the wide tuning range and many other unique advantages. So they are widely used in optical fiber communication, fiber optic sensing and all-optical signal processing.The fiber ring laser based on the semiconductor optical amplifier (SOA) is widely used for optical communications and optical fiber sensing, because it can be tuned at an ultra high speed up to Mega Hertz. The steady-state model and segmentation algorithm are employed to study the amplified spontaneous emission (ASE) properties of the SOA, then two kinds of the tunable ring lasers based on SOA (SOA-TRL) are investigated with the Gaussian or FP filter. The evolution of the output spectra and the peak power is demonstrated with the round trip of the light traveling in the ring cavity, which shows us the lasing process from the ASE to laser. It shows that the FP filter can improve the wavelength tuning speed because the SOA-TRL with an FP filter can establish the laser within only a few round trips, and it could be designed for some high speed applications. Semiconductor optical amplifier-based ring cavity laser (SOA-RL), which has been widely used in optical communications, optical fiber sensing, and bio-photonics fields, can be tuned at an ultra high speed up to Mega Hertz over100nm bandwidth range with high SNR and flatness output. A steady-state model and segmentation algorithms are employed to investigate the gain spectra of the SOA and the laser wavelength of the SOA-RL when the SOA is driven by some non-uniform injections, such as linear, quadratic, exponential, or square root functions. The results show that the laser wavelength changes slowly with the change of injection current when its average is greater, and there is a minimum value when the inject current is exponentially distributed along the SOA, which exhibits high wavelength stability. After a theoretical analysis we design and make a tunable ring laser prototype.