Generation of mode-locked square-shaped and chair-like pulse based on reverse saturable absorption effect of nonlinear multimode interference

et al. 2021

Adv Materials Inter

optical computers, optical switches, pulsed laser generation, optical sensors, etc. As the fundamental information carrier of NLO, nonlinear optical materials have attracted great attention since the advent of the first laser and always been the research hotspot for material and optical scientists. In the last two decades, 2D materials, representative of the main including graphene, [1-3] topological insulators (TIs), [4-6] transition metal disulfides (TMDs) [7,8] and black phosphorus (BP), [9-11] have experienced an explosive growth because of the advantages of exotic optical, electronic, chemical, and mechanical properties that much differ from their bulk counterparts. Especially, the low dimensions and distinctive nonlinear optical properties make them strongly meet the ever-increasing demand and widely used in high efficiency, compactness, broadband optoelectronic and photonic devices, broadband all-optical modulator, optical frequency conversion, pulsed laser generation, surface plasmonic, and so on. [12-19] However, there are still some disadvantages for the current 2D materials. For example, the gapless band structure and relative low light absorption of graphene limit its extensive applications; [20,21] the band gap of TMDs (1.0-2.0 eV) indicates they cannot be available in mid-infrared wavelength range; [22,23] and easy oxidation is the biggest obstacle for practical applications of BP. [24,25] Therefore, it is still an urgent demand to explore promising novel 2D nonlinear optical materials. Recently, 2D MXenes have been extensively studied due to the unique optical and electronic properties. [26,27] MXene represents a large family of 2D transition metal carbides, carbonitrides, and nitrides, with the general formula of M n+1 X n T n (n = 1-3), where M represents a transition metal (e.g., Ti, Mo, Nb), X for either C and/or N, and T is the surface functional group (e.g.,-OH,-O, and-F). [28,29] Until now, more than 30 varieties of 2D MXenes have been synthesized and theoretically and experimentally studied, [30-34] revealing the outstanding features of metallic conductivity, large electric capacity, high mechanical strength, tunable band gap, high stability, high optical transparency, and large optical nonlinearities of MXenes. [35,36] Nb 2 C is a newly discovered 2D MXene with special band structure near the Fermi level, showing the great potential applications as electrode materials Niobium carbide (Nb 2 C), a newly developed 2D MXene material, has attracted much attention due to its outstanding electronic and optical properties. In this work, few-layer 2D Nb 2 C nanosheets are synthesized by magnetron sputtering deposition method. Z-scan measurements with pump source operating at 1.0 µm are performed to study the third-order nonlinear optical response, revealing excellent light modulation capabilities of 2D Nb 2 C. The effective nonlinear absorption coefficient (β eff ≈-10 5 cm GW-1) caused by saturable absorption effect is determined to be two orders of magnitude larger than that induced by reverse sat...

Section: Third-order Nonlinear Optical Response Of 2d Nb 2 C Nanosheetsmentioning

confidence: 99%

“…In addition, the saturable absorption and reverse‐saturable absorption coexistence should be available for SWP laser generation. [ 57 ]…”

Section: Third‐order Nonlinear Optical Response Of 2d Nb2c Nanosheetsmentioning

confidence: 99%

Third‐Order Nonlinear Optical Response of Few‐Layer MXene Nb₂C and Applications for Square‐Wave Laser Pulse Generation

Liu

et al. 2021

Adv Materials Inter

“…In all-normal-dispersion (1 μm waveband) [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ] and the anomalous-dispersion domain (1.5 μm, 2 μm) [ 29 , 30 , 31 , 32 , 33 , 34 ], the lasers based on NL-MMI as SA have been studied by many scholars. In 2018, Tegin et al used NL-MMI mechanism for the first time to realize mode-locking operation in the 1 μm region [ 19 ].…”

Section: Introductionmentioning

confidence: 99%

Dispersion Management Nonlinear Multimode Interference Mode-Locked Ytterbium Fiber Laser

Qiu

2023

Nanomaterials

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.

“…In recent years, nonlinear multimode interference technology based on graded-index multimode fiber overcomes existing deficiencies of the present SAs, however, it requires a seriously specific length of nonlinear multimode fiber 17 – 19 nonlinear polarization evolution (NPE) has low environmental stability, 20 – 22 and nonlinear amplifying loop mirror cannot be easily self-starting 23 – 25 Because the modulation depth of these traditional SAs is difficult to exceed 70%, all the above mode-locked devices belong to the non-ideal SAs.…”

Section: Introductionmentioning

confidence: 99%

Recent advance of high-energy ultrafast mode-locked oscillators based on Mamyshev mechanism with different starting modes

Bai

et al. 2022

Opt. Eng.

The nonlinear effect of fiber limits the further increase in pulse energy, and Mamyshev oscillator shows outstanding advantages in managing nonlinearity in waveguide medium, which is now associated with high peak power and high pulse energy. The potential applications of these laser sources based on Mamyshev mechanism have facilitated aggressive research and innovative ideas by researchers around the world. Here, we focus on the modelocked principle and starting dynamics of Mamyshev oscillator. The review of Mamyshev technology is summarized from two starting modes of seed source injection and self-starting. Initial research and significant progress in this field, plus new insights and challenges of Mamyshev oscillator for ultrafast fiber laser technology are analyzed.