Giant-chirp oscillator for ultra-large net-normaldispersion fiber lasers

Abstract

We report on the experimental observations for giant-chirped dissipative solitons emitted from a passively mode-locked fiber laser, which has ultra-large normal cavity dispersion. Two types of solitons coexist in the same cavity and evolve with different spectrum shapes, one of which is exhibited as a rectangular-spectrum profile and the other is as a bell-spectrum profile. Both are highly chirped due to the positively nonlinear effect together with strong normal dispersion. The maximal time-bandwidth product of solitons reported here can be as large as 236.3, which is far larger than 0.315 for the classical solitons. The dynamic evolution of solitons versus pump power is demonstrated. The experimental results suggest that the nonlinear polarization rotation and the gain filtering effect dominate the pulse-shaping alternately, which lead to the spectrum profile transforming. With further increasing the pump power, the proposed laser emits multiple pulses one by one, and the number of pulses can be up to five at the pump power of ∼ 505 mW.

Formation and evolution of passively mode-locked fiber soliton lasers operating in a dual-wavelength regime

“…The generation and evolution of ultrashort pulses are rich and fascinating subjects of nonlinear optics [1][2][3][4][5][6]. Due to the intrinsic stability, optical solitons can propagate undistorted over long distances and have been widely used in fiber-optic communications and signal processing [7].…”

Actively Q-switched mode-locked Yb-doped fiber laser with high mode-locking contrast

“…In addition to the ultrashort pulse generation, low repetition rate and high energy pulses generation in passive mode locked (ML) YDFL and EDFL is inves tigated widely that can be operated in all normal dis persion or net normal dispersion region [15][16][17][18][19][20][21][22][23]. Besides, Q switching operation is another focus in YDFLs since the relatively long upper state life time of Yb ions can help the storage of energy from effi cient diode pumping sources [24,25].…”

Generation of bidirectional stretched pulses in a nanotube-mode-locked fiber laser

“…Passively mode-locked fiber lasers are attractive for many applications in fields of fiber optical communications [1,2], spectroscopy [3], and nonlinear optics [4,5], because they can provide the ultrafast pulses [6,7], the multiple wavelengths [8,9], and ultranarrow laser source [10]. Various techniques, such as nonlinear polarization rotation (NPR) [11][12][13][14], nonlinear amplifier loop mirror (NALM) [15], semiconductor saturable absorber mirror (SESAM) [16,17], single-walled carbon nanotubes (SWNTs) [6,[18][19][20], graphene [21,22], and graphene-nanotube mixtures [23] have been exploited for passive mode locking.…”