Development of linear cavity fiber lasers for ultrashort pulse generation with high repetition rate

• Main Author: Li, Nong.
• Other Authors: Chow Kin Kee
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/54353
• Institution: Nanyang Technological University

Mode-locked fiber lasers are able to generate transform-limited optical pulses in picosecond and sub-picosecond regimes. The fiber lasers are usually passively mode-locked using a saturable absorber such as saturable Bragg reflectors (SBRs), SESAM (semiconductor saturable absorber mirror), and nonlinear optical loop mirrors. There is a number of qualities that make the passive mode-locked fiber lasers attractive for ultrashort pulse generation, such as the generation of ultra short optic pulses in picosecond or sub-picosecond, their compact and rugged fabrications, and no requirement of active modulators. Moreover, they can also be worked with tele-communication components, and their output is compatible with telecom systems. Passively mode-locked fiber lasers are treated as one of the best optical sources in the contemporary society. The ultrashort pulse train with high repetition rate generated by passive mode-locked fiber lasers have wide application and the studies in this topic is on the way. It is not only attractive in fundamental scientific researches, but also in practical application. It can be used in super-continuum generation that is useful in communication systems. Moreover, due to its unique characteristic of high peak intensity, broad spectrum and high repetition rate, ultrashort pulse with high repetition rate is now applied in biological tissue processing, sensing, machining, cutting and so on. There are a lot of parameters that affect the output pulse, such as the fiber length, cavity loss, dispersion and the fiber nonlinearity. In this project, I will study both the ring and the linear cavity of passive mode-locked fiber lasers and find the optimum parameters for high-repetition-rate ultrashort pulse generation in linear passive mode-locked fiber lasers.