Stable Formation of Multiple Solitons in an Optical Microresonator Assisted by Saturable Absorption

Abstract Metallic 2D materials can be promising saturable absorbers for ultrashort pulsed laser production in the long wavelength regime. However, preparing and manipulating their 2D structures without layer stacking have been nontrivial. Using a combined experimental and theoretical approach, we demonstrate here that a metallic titanium carbide (Ti3C2Tx), the most popular MXene 2D material, can have excellent nonlinear saturable absorption properties even in a highly stacked state due to its intrinsically existing surface termination, and thus can produce mode-locked femtosecond pulsed lasers in the 1.9-μm infrared range. Density functional theory calculations reveal that the electronic and optical properties of Ti3C2Tx MXene can be well preserved against significant layer stacking. Indeed, it is experimentally shown that 1.914-μm femtosecond pulsed lasers with a duration of 897 fs are readily generated within a fiber cavity using hundreds-of-layer stacked Ti3C2Tx MXene saturable absorbers, not only being much easier to manufacture than mono- or few-layered ones, but also offering character-conserved tightly-assembled 2D materials for advanced performance. This work strongly suggests that as-obtained highly stacked Ti3C2Tx MXenes can serve as superb material platforms for versatile nanophotonic applications, paving the way toward cost-effective, high-performance photonic devices based on MXenes.

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Nonlinear Absorption and Ultrafast Dynamics of Ag Nanoparticle

Photonics ◽

10.3390/photonics8070233 ◽

2021 ◽

Vol 8 (7) ◽

pp. 233

Author(s):

Jijuan Jiang ◽

Jun Wang ◽

Tong Wu ◽

Yachen Gao

Keyword(s):

Silver Nanoparticles ◽

Time Constant ◽

Laser Intensity ◽

Photon Absorption ◽

Saturable Absorption ◽

Phonon Coupling ◽

Saturated Absorption ◽

Coupling Process ◽

Two Photon Absorption ◽

Two Photon

Resonant nonlinear optical absorption of silver nanoparticles was studied experimentally via open aperture Z-scan using 130 fs, 400 nm laser pulses. Experimental results show that, at low laser intensity, silver nanoparticles can exhibit saturated absorption. While at high laser intensity, it shows reverse saturated absorption. The saturable absorption is explained in terms of ground state plasmon bleaching, while the reverse saturable absorption is believed to be from two-photon absorption. Saturable optical intensity and two-photon absorption coefficient were obtained to be 1.3×1010 W/m2 and 3.3×10−10 m/W, respectively. The energy relaxation process of Ag nanoparticles after laser excitation was studied via pump-probe technique at 400 nm. Experimental results demonstrated that energy relaxation included electron-phonon coupling process with time constant τ1=(713±50) fs, and phonon-phonon coupling process with time constant τ2=(25.2±3) ps, respectively.

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MXenes for future nanophotonic device applications

Nanophotonics ◽

10.1515/nanoph-2020-0060 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1831-1853

Author(s):

Jaeho Jeon ◽

Yajie Yang ◽

Haeju Choi ◽

Jin-Hong Park ◽

Byoung Hun Lee ◽

...

Keyword(s):

Solar Cells ◽

Transition Metal ◽

Wide Spectrum ◽

Building Blocks ◽

Optoelectronic Device ◽

High Yield ◽

Saturable Absorption ◽

Nanophotonic Device ◽

Wide Range ◽

Device Applications

AbstractTwo-dimensional (2D) layers of transition metal carbides, nitrides, or carbonitrides, collectively referred to as MXenes, are considered as the new family of 2D materials for the development of functional building blocks for optoelectronic and photonic device applications. Their advantages are based on their unique and tunable electronic and optical properties, which depend on the modulation of transition metal elements or surface functional groups. In this paper, we have presented a comprehensive review of MXenes to suggest an insightful perspective on future nanophotonic and optoelectronic device applications based on advanced synthesis processes and theoretically predicted or experimentally verified material properties. Recently developed optoelectronic and photonic devices, such as photodetectors, solar cells, fiber lasers, and light-emitting diodes are summarized in this review. Wide-spectrum photodetection with high photoresponsivity, high-yield solar cells, and effective saturable absorption were achieved by exploiting different MXenes. Further, the great potential of MXenes as an electrode material is predicted with a controllable work function in a wide range (1.6–8 eV) and high conductivity (~104 S/cm), and their potential as active channel material by generating a tunable energy bandgap is likewise shown. MXene can provide new functional building blocks for future generation nanophotonic device applications.

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Enhancing Q-Switched Fiber Laser Performance Based on Reverse Saturable and Saturable Absorption Properties of CuCrO2 Nanoparticle-Polyimide Films

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c02762 ◽

2021 ◽

Author(s):

Yingtian Xu ◽

Hanfei Hu ◽

Hongda Wu ◽

Chongyang Xu ◽

He Zhang ◽

...

Keyword(s):

Fiber Laser ◽

Saturable Absorption ◽

Polyimide Films ◽

Absorption Properties ◽

Laser Performance

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Scalable Production of Boron Quantum Dots for Broadband Ultrafast Nonlinear Optical Performance

Nanomaterials ◽

10.3390/nano11030687 ◽

2021 ◽

Vol 11 (3) ◽

pp. 687

Author(s):

Shuolei Meng ◽

Qianyuan Chen ◽

Hongjian Lin ◽

Feng Zhou ◽

Youning Gong ◽

...

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Relaxation Time ◽

Nonlinear Optical ◽

Average Diameter ◽

Optical Devices ◽

Nonlinear Optical Properties ◽

Saturable Absorption ◽

Nonlinear Optical Susceptibility ◽

Tandem Structure

A simple and effective approach based on the liquid phase exfoliation (LPE) method has been put forward for synthesizing boron quantum dots (BQDs). By adjusting the interactions between bulk boron and various solvents, the average diameter of produced BQDs is about 7 nm. The nonlinear absorption (NLA) responses of as-prepared BQDs have been systematically studied at 515 nm and 1030 nm. Experimental results prove that BQDs possess broadband saturable absorption (SA) and good third-order nonlinear optical susceptibility, which are comparable to graphene. The fast relaxation time and slow relaxation time of BQDs at 515 nm and 1030 nm are about 0.394–5.34 ps and 4.45–115 ps, respectively. The significant ultrafast nonlinear optical properties can be used in optical devices. Here, we successfully demonstrate all-optical diode application based on BQDs/ReS2 tandem structure. The findings are essential for understanding the nonlinear optical properties in BQDs and open a new pathway for their applications in optical devices.

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Large Optical Nonlinearity of the Activated Carbon Nanoparticles Prepared by Laser Ablation

Nanomaterials ◽

10.3390/nano11030737 ◽

2021 ◽

Vol 11 (3) ◽

pp. 737

Author(s):

Yasin Orooji ◽

Hamed Ghanbari Gol ◽

Babak Jaleh ◽

Mohammad Reza Rashidian Vaziri ◽

Mahtab Eslamipanah

Keyword(s):

Electron Microscopy ◽

Activated Carbon ◽

Laser Ablation ◽

Carbon Nanoparticles ◽

Morphological Properties ◽

Excitation Wavelength ◽

Saturable Absorption ◽

Reverse Saturable Absorption ◽

High Porosity ◽

Nlo Properties

Carbon nanoparticles (CNPs) with high porosity and great optical features can be used as a luminescent material. One year later, the same group investigated the NLO properties CNPs and boron-doped CNPs by 532 nm and 1064 nm laser excitations to uncover the underlying physical mechanisms in their NLO response. Hence, a facile approach, laser ablation technique, was employed for carbon nanoparticles (CNPs) synthesis from suspended activated carbon (AC). Morphological properties of the prepared CNPs were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). UV-Vis and fluorescence (FL) spectra were used to optical properties investigation of CNPs. The size distribution of nanoparticles was evaluated using dynamic light scattering (DLS). The nonlinear optical (NLO) coefficients of the synthesized CNPs were determined by the Z-scan method. As a result, strong reverse saturable absorption and self-defocusing effects were observed at the excitation wavelength of 442 nm laser irradiation. These effects were ascribed to the presence of delocalized π-electrons in AC CNPs. To the best of our knowledge, this is the first study investigating the NLO properties of the AC CNPs.

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2D organic-inorganic hybrid perovskite materials for nonlinear optics

Nanophotonics ◽

10.1515/nanoph-2020-0038 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1787-1810 ◽

Cited By ~ 3

Author(s):

Xiao Han ◽

Yongshen Zheng ◽

Siqian Chai ◽

Songhua Chen ◽

Jialiang Xu

Keyword(s):

Nonlinear Optical ◽

Second Harmonic ◽

Low Cost ◽

Laser Pulses ◽

Structural Features ◽

Photon Absorption ◽

Saturable Absorption ◽

Research Attention ◽

Inorganic Hybrid ◽

Quantum Well Structures

AbstractTwo-dimensional (2D) organic-inorganic hybrid perovskites feature characteristics of inherent quantum-well structures and intriguing optoelectronic properties, and have therefore attracted enormous research attention for their optical applications in light emitting, sensing, modulation, and telecommunication devices. The low-cost and solution-processed fabrications as well as alternative organic spacer cations endue 2D hybrid perovskites with higher tunability in optical and photonic applications. In particular, they demonstrate distinguished nonlinear optical characters such as second-harmonic generation (SHG), two-photon absorption (2PA), and saturable absorption (SA) under the excitation of laser pulses. Here, we discuss the construction of the various sorts of 2D hybrid perovskites with different structural features. We have also highlighted some representative properties and applications of these 2D hybrid perovskites in both linear and nonlinear optical regimes.

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