Title :
Tunable High-Order Harmonic Mode-Locking in Yb-Doped Fiber Laser With All-Normal Dispersion
Author :
Zhu, Xiaojun ; Wang, Chinhua ; Liu, Shixin ; Zhang, Guiju
Author_Institution :
Key Lab. of Adv. Opt. Manuf. of Jiangsu Province, Soochow Univ., Suzhou, China
fDate :
5/1/2012 12:00:00 AM
Abstract :
A tunable high-order harmonic and passively mode-locked Yb-doped fiber laser with all-normal dispersion is demonstrated. Using the mode-locking mechanism of the nonlinear polarization evolution (NPE) effect and a cascade long period fiber grating (C-LPFG) as an all-fiber format spectral filter for the strong pulse shaping, a maximum of 14th-order harmonic mode-locked (HML) Yb-doped fiber laser can be tunably achieved with a repetition rate of 35.497 MHz compared with the fundamental repetition rate of 2.538 MHz, which is the highest harmonic mode-locked laser with all-normal dispersion so far. At the 14th HML output, the cavity supermodes are suppressed to 23 dB, and the pulses duration is 1.23 ns with a maximum pulse energy of 0.97 nJ.
Keywords :
diffraction gratings; fibre lasers; laser cavity resonators; laser mode locking; optical fibre dispersion; optical fibre polarisation; optical filters; optical pulse shaping; ytterbium; all fiber format spectral filter; all normal dispersion; cascade long period fiber grating; cavity supermode suppression; energy 0.97 nJ; fiber laser; nonlinear polarization evolution; passively mode locked laser; pulse shaping; time 1.23 ns; tunable high order harmonic mode locking; Cavity resonators; Dispersion; Harmonic analysis; Laser mode locking; Pump lasers; Ring lasers; Solitons; All-normal-dispersion; fiber laser; high-order harmonic mode-locked; long period grating;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2012.2188023
