title: Low-repetition-rate, high-energy, twin-pulse, passively mode locked Yb3+-doped fiber laser.
abstract: We report an all-normal-dispersion, low-repetition-rate, high-energy, twin-pulse, passively mode locked ytterbium-doped fiber laser. The mode-locking mechanism of the laser is based on nonlinear polarization evolution and strong pulse shaping with a cascade long-period fiber grating bandpass filtering in a highly chirped pulse. The laser generates a highly stable twin-pulse group with 248 ps and 296 ps duration simultaneously and maximum pulse energy of 26.8 nJ-each pulse at a 2.5445 MHz repetition rate. Energy quantization is observed, which demonstrates the nonparabolic nature of these pulses. The laser can also work in third-harmonic mode locking with 17.8 nJ energy (at a repetition rate of 7.65 MHz and pulse width of 780 ps).
authors.affiliation: Institute of Modern Optical Technologies, Soochow University, Suzhou, Jiangsu, China. Liudf2000@hotmail.com
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Liu
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Zhu
authors.forename: Chinhua
authors.initials: C
authors.lastname: Wang
authors.forename: Jianjun
authors.initials: J
authors.lastname: Yu
authors.forename: Danfeng
authors.initials: D
authors.lastname: Hu
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D007834:Lasers; D012031:Refractometry / Q000295:instrumentation*