Wavelength-dependent nonlinear absorption of gold nanobipyramids with large saturable modulation depth

2022 ◽  
Vol 147 ◽  
pp. 107686
Author(s):  
Shuang Chen ◽  
Yachen Gao ◽  
Ruipeng Niu ◽  
Wenfa Zhou ◽  
Yuxiao Wang ◽  
...  
Keyword(s):  
Nonlinear Absorption ◽  
Modulation Depth ◽  
Gold Nanobipyramids

scholarly journals Nonlinear Absorption Properties of Cr2Ge2Te6 and Its Application as an Ultra-Fast Optical Modulator

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 789 ◽  
Author(s):  
Peng-fei Ma ◽  
Wei Lin ◽  
Hua-nian Zhang ◽  
Shan-hui Xu ◽  
Zhong-min Yang
Keyword(s):  
Nonlinear Absorption ◽  
Modulation Depth ◽  
Ring Cavity ◽  
Optical Modulator ◽  
Optical Modulators ◽  
Absorption Properties ◽  
Stable Mode ◽  
Power Pulse ◽  
Saturation Intensity ◽  
Er Doped

In this manuscript, the nonlinear absorption properties of Cr2Ge2Te6 and its application in ultra-fast optical modulation are investigated. Typical parameters, namely, nonlinear absorption coefficient (β), saturation intensity, and modulation depth are measured to be ~1.66 × 10−9 m/W, 15.3 MW/cm2, and 5.8%, respectively. To investigate the feasibility of using the Cr2Ge2Te6 as an ultra-fast optical modulator, a ring-cavity passively mode-locked Er-doped fiber laser has been constructed. The output power/pulse, duration/pulse, and repetition rate/signal-to-noise ratios for the stable mode-locked operation are 2.88 mW/881 fs/19.33 MHz/48 dB, respectively, which proves that the Cr2Ge2Te6 has outstanding nonlinear optical properties and advantages in performing as an ultra-fast optical modulator. Further, the experimental results provide valuable references and open new avenues for developing two-dimensional, material-based, ultra-fast optical modulators and advanced photonic devices based on Cr2Ge2Te6.

scholarly journals Nonlinear Optical Properties of Zirconium Diselenide and Its Ultra-Fast Modulator Application

Nanomaterials ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1419 ◽  
Author(s):  
Wang ◽  
Zheng ◽  
Guo ◽  
Chen ◽  
Zhang ◽  
...  
Keyword(s):  
Nonlinear Absorption ◽  
Modulation Depth ◽  
Ring Cavity ◽  
Maximum Output Power ◽  
Mode Locking ◽  
Saturable Absorption ◽  
Maximum Output ◽  
Transition Metal Dichalcogenide ◽  
Absorption Properties ◽  
Zirconium Diselenide

Recently, two-dimensional (2D) materials have been widely studied by researchers due to their exceptional 2D structure and excellent optical characteristics. As one of the typically-layered 2D transition metal dichalcogenide (TMD) semiconductors from group IVB with a bandgap value of 0.9–1.2 eV (bulk to monolayer), the characteristics of zirconium diselenide (ZrSe2) have already been extensively investigated in many fields. However, the nonlinear absorption properties of ZrSe2 in ultra-fast lasers have not been previously demonstrated. In this work, we measured various parameters in order to investigate the characteristics of the nonlinear saturable absorption of ZrSe2. A ZrSe2–polyvinyl alcohol (PVA) film was successfully prepared, which was employed as a saturable absorber (SA) to demonstrate, for the first time, an erbium (Er)-doped passive mode-locking fiber laser with a ring cavity. The saturation intensity of the ZrSe2–PVA film-type SA is 12.72 MW/cm2, while its modulation depth is 2.3%. The stable soliton state with a maximum output power of 11.37 mW and a narrowest monopulse duration of 12.5 ps at a repetition frequency of 21.22 MHz was detected. The experimental results conclusively proved that ZrSe2, with its suitable bandgap value and excellent nonlinear absorption properties, as well as its high damage threshold, should have extensive potential applications within the field of ultra-fast pulse lasers.

scholarly journals Manipulation of epsilon-near-zero wavelength for the optimization of linear and nonlinear absorption by supercritical fluid

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiaye Wu ◽  
Xuanyi Liu ◽  
Haishi Fu ◽  
Kuan-Chang Chang ◽  
Shengdong Zhang ◽  
...  
Keyword(s):  
Supercritical Fluid ◽  
Indium Tin Oxide ◽  
Nonlinear Absorption ◽  
Modulation Depth ◽  
Saturable Absorption ◽  
Time Saving ◽  
Nanophotonic Devices ◽  
Absorption Performance ◽  
Linear And Nonlinear ◽  
Epsilon Near Zero

AbstractWe introduce supercritical fluid (SCF) technology to epsilon-near-zero (ENZ) photonics for the first time and experimentally demonstrate the manipulation of the ENZ wavelength for the enhancement of linear and nonlinear optical absorption in ENZ indium tin oxide (ITO) nanolayer. Inspired by the SCF’s applications in repairing defects, reconnecting bonds, introducing dopants, and boosting the performance of microelectronic devices, here, this technique is used to exploit the influence of the electronic properties on optical characteristics. By reducing oxygen vacancies and electron scattering in the SCF oxidation process, the ENZ wavelength is shifted by 23.25 nm, the intrinsic loss is reduced by 20%, and the saturable absorption modulation depth is enhanced by > 30%. The proposed technique offers a time-saving low-temperature technique to optimize the linear and nonlinear absorption performance of plasmonics-based ENZ nanophotonic devices.

scholarly journals Double-layer graphene on photonic crystal waveguide electro-absorption modulator with 12 GHz bandwidth

Nanophotonics ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 2377-2385 ◽  
Author(s):  
Zhao Cheng ◽  
Xiaolong Zhu ◽  
Michael Galili ◽  
Lars Hagedorn Frandsen ◽  
Hao Hu ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Double Layer ◽  
Slow Light ◽  
Modulation Depth ◽  
Photonic Crystal Waveguide ◽  
Optical Modulators ◽  
Layer Graphene ◽  
Silicon Photonic ◽  
On Chip ◽  
Silicon Based

AbstractGraphene has been widely used in silicon-based optical modulators for its ultra-broadband light absorption and ultrafast optoelectronic response. By incorporating graphene and slow-light silicon photonic crystal waveguide (PhCW), here we propose and experimentally demonstrate a unique double-layer graphene electro-absorption modulator in telecommunication applications. The modulator exhibits a modulation depth of 0.5 dB/μm with a bandwidth of 13.6 GHz, while graphene coverage length is only 1.2 μm in simulations. We also fabricated the graphene modulator on silicon platform, and the device achieved a modulation bandwidth at 12 GHz. The proposed graphene-PhCW modulator may have potentials in the applications of on-chip interconnections.

scholarly journals VS2 as saturable absorber for Q-switched pulse generation

Nanophotonics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 2569-2576 ◽  
Author(s):  
Lu Li ◽  
Lihui Pang ◽  
Qiyi Zhao ◽  
Yao Wang ◽  
Wenjun Liu
Keyword(s):  
Saturable Absorber ◽  
Nonlinear Optical ◽  
Modulation Depth ◽  
Signal To Noise Ratio ◽  
Transition Metal Dichalcogenides ◽  
Laser Cavity ◽  
Pulse Generation ◽  
High Signal ◽  
Power Pulse ◽  
Metal Dichalcogenides

AbstractTransition metal dichalcogenides have been widely utilized as nonlinear optical materials for laser pulse generation applications. Herein, we study the nonlinear optical properties of a VS2-based optical device and its application as a new saturable absorber (SA) for high-power pulse generation. Few-layer VS2 nanosheets are deposited on the tapered region of a microfiber to form an SA device, which shows a modulation depth of 40.52%. After incorporating the microfiber-VS2 SA into an Er-doped fiber laser cavity, passively Q-switched pulse trains could be obtained with repetition rates varying from 95 to 233 kHz. Under the pump power of 890 mW, the largest output power and shortest pulse duration are measured to be 43 mW and 854 ns, respectively. The high signal-to-noise ratio of 60 dB confirms the excellent stability of the Q-switching state. To the best of our knolowdge, this is the first illustration of using VS2 as an SA. Our experimental results demonstrate that VS2 nanomaterials have a large potential for nonlinear optics applications.

Self-focusing of cosh-Gaussian laser beam in collisional plasma: effect of nonlinear absorption

2021 ◽  
Author(s):  
Naveen Gupta ◽  
Sandeep Kumar ◽  
A Gnaneshwaran ◽  
Sanjeev Kumar ◽  
Suman Choudhry
Keyword(s):  
Laser Beam ◽  
Nonlinear Absorption ◽  
Collisional Plasma ◽  
Gaussian Laser Beam ◽  
Self Focusing ◽  
Plasma Effect

scholarly journals Dynamics of carbon nanotube-based mode-locking fiber lasers

Nanophotonics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 2731-2761 ◽  
Author(s):  
Lin Huang ◽  
Yusheng Zhang ◽  
Xueming Liu
Keyword(s):  
Carbon Nanotube ◽  
Fiber Lasers ◽  
Modulation Depth ◽  
Laser System ◽  
Physical Nature ◽  
Mode Locking ◽  
Environmental Stability ◽  
Saturation Intensity ◽  
Soliton Dynamics ◽  
Deep Modulation

AbstractCarbon nanotube (CNT) can work as excellent saturable absorber (SA) due to its advantages of fast recovery, low saturation intensity, polarization insensitivity, deep modulation depth, broad operation bandwidth, outstanding environmental stability, and affordable fabrication. Its successful application as SA has promoted the development of scientific research and practical application of mode-locked fiber lasers. Besides, mode-locked fiber laser constitutes an ideal platform for investigating soliton dynamics which exhibit profound nonlinear optical dynamics and excitation ubiquitous in many fields. Up to now, a variety of soliton dynamics have been observed. Among these researches, CNT-SA is a key component that suppresses the environmental perturbation and optimizes the laser system to reveal the true highly stochastic and non-repetitive unstable phenomena of the initial self-starting lasing process. This review is intended to provide an up-to-date introduction to the development of CNT-SA based ultrafast fiber lasers, with emphasis on recent progress in real-time buildup dynamics of solitons in CNT-SA mode-locked fiber lasers. It is anticipated that study of dynamics of solitons can not only further reveal the physical nature of solitons, but also optimize the performance of ultrafast fiber lasers and eventually expand their applications in different fields.

scholarly journals A 40 Mb/s VLC System Reusing an Existing Large LED Panel in an Indoor Office Environment

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1697
Author(s):  
Xicong Li ◽  
Zabih Ghassemlooy ◽  
Stanislav Zvánovec ◽  
Paul Anthony Haigh
Keyword(s):  
Modulation Depth ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Data Communication ◽  
Experimental System ◽  
Digital Signal ◽  
Visible Light Communication ◽  
Cost Driver ◽  
Limiting Factors ◽  
Light Sources

With advances in solid-state lighting, visible light communication (VLC) has emerged as a promising technology to enhance existing light-emitting diode (LED)-based lighting infrastructure by adding data communication capabilities to the illumination functionality. The last decade has witnessed the evolution of the VLC concept through global standardisation and product launches. Deploying VLC systems typically requires replacing existing light sources with new luminaires that are equipped with data communication functionality. To save the investment, it is clearly desirable to make the most of the existing illumination systems. This paper investigates the feasibility of adding data communication functionality to the existing lighting infrastructure. We do this by designing an experimental system in an indoor environment based on an off-the-shelf LED panel typically used in office environments, with the dimensions of 60 × 60 cm2. With minor modifications, the VLC function is implemented, and all of the modules of the LED panel are fully reused. A data rate of 40 Mb/s is supported at a distance of up to 2 m while using the multi-band carrierless amplitude and phase (CAP) modulation. Two main limiting factors for achieving higher data rates are observed. The first factor is the limited bandwidth of the LED string inside the panel. The second is the flicker due to the residual ripple of the bias current that is generated by the panel’s driver. Flicker is introduced by the low-cost driver, which provides bias currents that fluctuate in the low frequency range (less than several kilohertz). This significantly reduces the transmitter’s modulation depth. Concurrently, the driver can also introduce an effect that is similar to baseline wander at the receiver if the flicker is not completely filtered out. We also proposed a solution based on digital signal processing (DSP) to mitigate the flicker issue at the receiver side and its effectiveness has been confirmed.

scholarly journals Wavelength-Dependent Nonlinear Absorption in Palladium Nanoparticles

2021 ◽  
Vol 11 (4) ◽  
pp. 1640
Author(s):  
Chunyu Chen ◽  
Jun Wang ◽  
Yachen Gao
Keyword(s):  
Surface Plasmon Resonance ◽  
Excitation Energy ◽  
Systematic Study ◽  
Nonlinear Absorption ◽  
Palladium Nanoparticles ◽  
Excitation Wavelength ◽  
Saturated Absorption ◽  
Multi Wavelength ◽  
Resonant Region ◽  
Absorption Characteristics

This paper aims to study the nonlinear absorption characteristics of palladium nanoparticles (PdNPs) at off-resonant wavelengths. For this purpose, multi-wavelength (500–650 nm) nanosecond Z-scan technique was used. The experimental results indicate that saturated absorption (SA) and the transition from SA to reverse saturated absorption (RSA) can occur, and depends on the excitation wavelength and energy. When the excitation wavelength is constant, with the increase of excitation energy, PdNPs change from SA to RSA. When the excitation energy is constant, with the excitation wavelength approaching surface plasmon resonance (SPR), PdNPs change from SA to RSA. This phenomenon of SA and RSA under multi-wavelength excitation in the off-resonant region provides a supplement for the systematic study of the nonlinear absorption of PdNPs.

Sign in / Sign up

Export Citation Format

Share Document