Hybrid structure based on no-core and graded-index multimode fibers as saturable absorber for a self-starting mode-locked Yb-doped fiber laser
TL;DR: The results show that the NCF-GIMF-based SA can be used as an effective photonic device for high energy wave breaking free pulse generation.
Abstract: We demonstrate an all-fiber ytterbium (Yb)-doped mode-locked oscillator using a hybrid structure based on no-core fiber graded-index multimode fiber (NCF-GIMF) as the saturable absorber (SA). The proposed SA exhibits unique characteristics such as large-power tolerance, high modulation depth of 24.7%, and low saturation intensity of 11.01MW/cm2, which help to achieve a stable mode-locking operation. The all-normal and self-starting oscillator generates stable ultrafast pulses with a repetition rate of 21.35 MHz, pulse energy/average output power of 120 pJ/2.7 mW, and a pulse duration of 2.4 ps at a central wavelength of 1034.2 nm. The output pulses are then dechirped to 300 fs using an external grating compressor and possess high stability with a radio frequency spectrum of 58 dB. These results show that the NCF-GIMF-based SA can be used as an effective photonic device for high energy wave breaking free pulse generation.
Citations
More filters
TL;DR: In this article , the authors review the research status of the mechanism and technology of all-fiber mode-locked ultrafast laser with multimode fiber based saturable absorber.
9 citations
TL;DR: In this article , a composite mode-locked mechanism based on the Carbon nanotube (CNT) film sandwiched between the multimode fiber (MMF) connectors was proposed and demonstrated.
1 citations
TL;DR: In this article , the dispersion management of a mode-locked fiber laser is carried out by adjusting the distance between the grating pair, which typically ranges from soliton state in the anomalous dispersion regime to the dissipative soliton format in the normal one.
Abstract: Dispersion management plays an important role in improving the output performance of a mode-locked fiber laser. Therefore, dispersion management is carried out by introducing the grating pair in our experiment. Through adjusting the distance between the grating pair, mode-locked pulses corresponding to different dispersion regimes can be realized, which typically range from soliton state in the anomalous dispersion regime to the dissipative soliton format in the normal dispersion regime. Furthermore, tunable spectrum distribution can be achieved by adjusting two intra-cavity polarization controllers. The proposed dispersion management method complements mode-locking techniques based on nonlinear multimode interference (NL-MMI). The laser can operate with self-start mode locking stably and is useful for practice applications.
1 citations
01 Mar 2022
TL;DR: In this article , the authors explored the potential use of graded-index multimode fiber (GIMF) in a nonlinear absorbing loop mirror (NAbLM) as an artificial saturable absorber for ultrashort pulse generation.
Abstract: This investigation explores the potential use of graded-index multimode fiber (GIMF) in a nonlinear absorbing loop mirror (NAbLM) as an artificial saturable absorber for ultrashort pulse generation. The saturable absorption mechanism of GIMF-NAbLM was based on a combination of nonlinear phase shift and multimodal interference that was satisfied by the asymmetric positioning of the GIMF in the single-mode fiber loop mirror. The proposed saturable absorber was integrated in a mode-locked thulium-doped fiber laser with figure-of-eight cavity. A noise-like pulse of 164 fs spike pulse duration at 1950 nm central wavelength was attained in the net anomalous dispersion with a 10 m long GIMF. The GIMF-NAbLM structure demonstrates immense prospects as an effective saturable absorption device for generating stable ultrashort pulse in the 2 µm region due to its simplicity.
1 citations
TL;DR: In this article , an all-normal dispersion configuration for the ytterbium doped fiber laser mode-locked by cascaded nonlinear multimode interference (MMI) effect is presented.
Abstract: We report dark–bright pulse pair generation from the ytterbium doped fiber laser mode-locked by cascaded nonlinear multimode interference (MMI) effect under an all-normal dispersion configuration. The MMI is implemented in a step index single mode–multimode–single mode fiber structure. The combination of two MMI structures, acting like a saturable absorber, has been used for stable mode-locking operation in the resonator. By adjusting the polarization controller attached to one of the MMI structure, stable dark–bright pulses are observed at fundamental, second and third harmonic repetition rates. The optical spectrum of the dark–bright pulses is doubly peaked at 1036.6 and 1040.6 nm with a spectral width ∼0.7 nm. The width of the dark pulses varied from 72 to 50 ns and that of the bright pulses from 30 to 14 ns when the pump power is increased from 102 to 170 mW at the fundamental repetition rate mode-locking. The darkness of the dark and intensity of bright pulses increase with the pump power. Dark and bright pulses in the pair are resolved by placing a polarizing component confirming their vector nature.
References
More filters
TL;DR: In this article, a Tm-doped calcium lithium niobium gallium garnet (Tm:CLNGG) laser was experimentally demonstrated with MoS2 as saturable absorber.
Abstract: With MoS2 as saturable absorber, passive Q-switching and Q-switched mode-locking operations of a Tm-doped calcium lithium niobium gallium garnet (Tm:CLNGG) laser were experimentally demonstrated. The Q-switched laser emitted a maximum average output power of 62 mW and highest pulse energy of 0.72 μJ. Q-switched mode locking was also obtained in the experiment. The research results will open up applications of MoS2 at the mid-infrared wavelength.
110 citations
TL;DR: In this paper, a mode-locked Tm-Ho-codoped fiber laser was demonstrated at the wavelength beyond 2.8 μm with a pulse energy of 0.41 nJ and a pulse duration of 1.1 ps.
Abstract: A mode-locked Tm-Ho-codoped fiber laser is reported, which is the first demonstration of a mode-locked fiber laser oscillator at the wavelength beyond 2 μm . The laser was built with a piece of newly developed Tm-Ho-codoped dc silicate fiber and a Sb-based semiconductor saturable absorber mirror (SESAM). When cladding pumped with a laser diode at 0.8 μm, the fiber laser generates mode-locked solitons at 2.06 μm with a pulse energy of 0.41 nJ and pulse duration of 1.1 ps.
106 citations
TL;DR: In this article, an all-fiber passively mode-locked thulium-doped fiber ring oscillator is constructed using optically deposited few layer graphene micro-sheets as the saturable absorber.
Abstract: An all-fiber passively mode-locked thulium-doped fiber ring oscillator is constructed using optically deposited few layer graphene micro-sheets as the saturable absorber (SA). The mode-lock operation was achieved by 130-mW pump power at 1.5-μm. The fiber oscillator produces 2.1-ps soliton pulse output with 80-pJ per pulse energy. The 3-dB bandwidth of the laser output was measured as 2.2-nm. The RF signal-to-noise ratio of 50-dB and sub 20-Hz 3-dB bandwidth of the laser output confirms the stable laser operation with low time jittering. This paper shows that graphene can be an effective saturable absorber for the development of mid-IR fiber mode-locked laser.
102 citations
TL;DR: In this paper, a mode-locked all-fiber laser based on the nonlinear multimode interference (NL-MMI) effect of the graded-index multimode fiber (GIMF) is proposed and demonstrated.
Abstract: A mode-locked all-fiber laser based on the nonlinear multimode interference (NL-MMI) effect of the graded-index multimode fiber (GIMF) is proposed and demonstrated. The saturable absorber (SA) used in the laser consists of a step-index multimode fiber (SIMF) connected by a GIMF. Compared with the theoretically proposed SMF–GIMF–SMF structure, the introduction of the SIMF eliminates the restriction on the length of the GIMF and provides a more flexible method of making an SA based on the NL-MMI. Through bending the device to a certain state, the modulation depth of the SA was measured to be 3.16%. The mode-locked laser output pulses have the pulsewidth of ∼446 fs, the bandwidth of 4.48 nm, and the fundamental repetition rate of 11.73 MHz. This versatility and simplicity of the SA device combined with the possibility of scaling the pulse energy in the large-mode-area double-clad fiber laser make it highly attractive in ultrafast photonics.
95 citations
TL;DR: In this article, a solid-core ytterbium-doped photonic bandgap fiber laser passively mode-locked with a semiconductor saturable absorber is demonstrated.
Abstract: We demonstrate a solid-core ytterbium-doped photonic bandgap fiber laser passively mode-locked with a semiconductor saturable absorber. Gain and anomalous dispersion simultaneously provided by the photonic crystal fiber allow for an all-fiber subpicosecond soliton oscillator. We also discuss the effect of higher-order dispersion in photonic bandgap fiber on laser performance.
81 citations