| Summary: | 碩士 === 國立交通大學 === 顯示科技研究所 === 98 === An ultrafast all-normal dispersion mode-locked ytterbium (Yb) doped fiber laser with no practical, optical bandpass filter is developed and the stabilization of its repetition frequency is achieved by using phase locked loop (PLL) technique. Polarization-additive pulse mode-locking (P-APM) method is employed to achieve mode-locking. The all-normal-dispersion ocsillator generates 12.8 ps (FWHM) laser pulses with 160 mW average power at 40 MHz repetition rate. Nearly triple power amplification (~ 420 mW) is achieved after forward pumped amplification and the pulsewidth of amplified pulses are externally compressed in the hollow-core photonic crystal fiber to 300 femtoseconds. The compressed laser pulses are sent into a solid core photonic crystal fiber (PCF) to generate supercontinuum (SC). The bandwidth of generated SC covers from 960 nm to 1370 nm and additionally, Cherenkov radiation at 344 nm, 429 nm, and 502 nm are observed. Finally, PLL technique is used to stabilize the repetition frequency of the mode-locked laser and the measured tracking stability of the out-of-loop repetition rate of our laser is at 1 s.
|
|---|
