Facile Synthesis of Monodispersed Titanium Nitride Quantum Dots for Harmonic Mode-Locking Generation in an Ultrafast Fiber Laser

Abstract

As a member of the transition metal nitride material family, titanium nitride (TiN) quantum dots (QDs) have attracted great attention in optical and electronic fields because of their excellent optoelectronic properties and favorable stability. Herein, TiN QDs were synthesized and served as a saturable absorber (SA) for an ultrafast fiber laser. Due to the strong nonlinear optical absorption characteristics with a modulation depth of ~33%, the typical fundamental mode-locked pulses and harmonics mode-locked pulses can be easily obtained in an ultrafast erbium-doped fiber laser with a TiN-QD SA. In addition, at the maximum pump power, harmonic mode-locked pulses with a repetition rate of ~1 GHz (164th order) and a pulse duration of ~1.45 ps are achieved. As far as we know, the repetition rate is the highest in the ultrafast fiber laser using TiN QDs as an SA. Thus, these experimental results indicate that TiN QDs can be considered a promising material, showing more potential in the category of ultrafast laser and nonlinear optics.

Bi2O2Te Nanosheets Saturable Absorber‐Based Passive Mode‐Locked Fiber Laser: From Soliton Molecules to Harmonic Soliton

“…In addition, the performances of the proposed SA and SESAM [ 49 ] as well as those of various reported typical 2D SA‐based (including graphene, [ 50 ] carbon nanotubes, [ 51 ] gold nanowires, [ 52 ] TIs, [ 53,54 ] transition metal dichalcogenides (TMDs), [ 55–58 ] Metal–organic frameworks (MOFs), [ 59 ] ferromagnetic insulators, [ 60 ] BP, [ 61 ] MXenes, [ 62 ] bismuthine, [ 63 ] tellurene, [ 64 ] and antimonene [ 65 ] ) passive mode‐locking fiber lasers are summarized in Table 1 . The HML based on the 2D MoSe 2 SA exhibited the highest repetition rate (3.27 GHz); however, the modulation depth and saturable intensity were both low.…”

“…It should be noted that the output harmonic pulses exhibited a higher repetition rate and excellent SNR under moderate pump power levels, which is preferable for engineering applications, including ultrahigh-speed optical time-division multiplexing systems, [46] ultrafast all-optical sampling, [47] and all-optical clock recovery. [48] In addition, the performances of the proposed SA and SESAM [49] as well as those of various reported typical 2D SA-based (including graphene, [50] carbon nanotubes, [51] gold nanowires, [52] TIs, [53,54] transition metal dichalcogenides (TMDs), [55][56][57][58] Metal-organic frameworks (MOFs), [59] ferromagnetic insulators, [60] BP, [61] MXenes, [62] bismuthine, [63] tellurene, [64] and antimonene [65] ) passive mode-locking fiber lasers are summarized in Table 1. The HML based on the 2D MoSe 2 SA exhibited the highest repetition rate (3.27 GHz); however, the modulation depth and saturable intensity were both low.…”

Preparation and pulsed fiber laser applications of emerging nanostructured materials

“…There are reports about the plasmonic metal nitrides and phosphides such as TiN, 364–366 InN, 367 and Cu 3− x P nanostructured materials 368 as the SAs for applications in passively mode-locked fiber lasers. For instance, Xian et al reported the passively mode-locked fiber laser centered at 1562 nm with pulsed duration down to 763 fs in EDFL by using the TiN nanoparticles as the SA in 2019 (Fig.…”

Transition Metal Nitrides for Electrocatalytic Application: Progress and Rational Design

“…As a kind of non-noble metal material, TMNs exhibit similar surface and adsorption properties to the VIII group of precious metals (such as Pt and Pd) because the atomic distance between metal atoms increases and the d-band center downshifts after the incorporation of nitrogen atoms [ 21 , 22 ]. Combined with attractive electrical conductivity, robust chemical stability, and remarkable mechanical robustness, TMNs have great potential as high-efficiency catalysts in various areas such as electrocatalysis, hydrogenation/desulfurization of fuel oil, synthesis/decomposition of ammonia, and other fields [ 23 , 24 , 25 , 26 ]. Moreover, their impressive chemical inertness and high corrosion resistance allow TMNs to be applied in a wide array of pH conditions for long periods, expanding the electrocatalytic application in various mediums [ 27 , 28 ].…”