scholarly journals Femtosecond Optical Nonlinearity of Nanodiamond Suspensions

2021 ◽  
Vol 11 (12) ◽  
pp. 5455
Author(s):  
Gennady M. Mikheev ◽  
Viatcheslav V. Vanyukov ◽  
Tatyana N. Mogileva ◽  
Konstantin G. Mikheev ◽  
Alexander N. Aleksandrovich ◽  
...  
Keyword(s):  
Optical Properties ◽  
Nonlinear Absorption ◽  
Optical Limiting ◽  
Optical Nonlinearity ◽  
Photon Absorption ◽  
Detonation Nanodiamonds ◽  
Saturable Absorption ◽  
Aqueous Suspensions ◽  
Saturation Intensity ◽  
High Pressure High Temperature

High pressure-high temperature (HP-HT) nanodiamonds and detonation nanodiamonds have unique optical properties and are promising materials for various applications in photonics. In this work, for the first time, comparative studies of the nonlinear optical properties of aqueous suspensions of HP-HT and detonation nanodiamonds under femtosecond laser excitation are performed. Using the z-scan technique, it was found that for the same laser pulse parameters HP-HT nanodiamonds exhibited optical limiting due to two-photon absorption while detonation nanodiamonds exhibited saturable absorption accompanied by short-term optical bleaching, revealing the different electronic-gap structures of the two types of nanodiamonds. The saturable absorption properties of detonation nanodiamonds are characterized by determining the saturable and non-saturable absorption coefficients, the saturation intensity, and the ratio of saturable to non-saturable losses. The nonlinear absorption in HP-HT nanodiamonds is described with the nonlinear absorption coefficient that decreases with decreasing concentration of nanoparticles linearly. The results obtained show the possibility of using aqueous suspensions of nanodiamonds for saturable absorption and optical limiting applications.

Enhanced luminescence and nonlinear optical properties of nanocomposites of ZnO–Cu

2008 ◽  
Vol 23 (11) ◽  
pp. 2836-2845 ◽  
Author(s):  
Litty Irimpan ◽  
V.P.N. Nampoori ◽  
P. Radhakrishnan
Keyword(s):  
Optical Properties ◽  
Nonlinear Absorption ◽  
Nonlinear Optical ◽  
Volume Fraction ◽  
Nonlinear Optical Properties ◽  
Visible Emission ◽  
Photon Absorption ◽  
Nonlinear Material ◽  
Saturable Absorption ◽  
Uv Emission

In this article, we present the spectral and nonlinear optical properties of ZnO–Cu nanocomposites prepared by colloidal chemical synthesis. The emission consisted of two peaks. The 385-nm ultraviolet (UV) peak is attributed to ZnO and the 550-nm visible peak is attributed to Cu nanocolloids. Obvious enhancement of UV and visible emission of the samples is observed and the strongest UV emission of a typical ZnO–Cu nanocomposite is over three times stronger than that of pure ZnO. Cu acts as a sensitizer and the enhancement of UV emission are caused by excitons formed at the interface between Cu and ZnO. As the volume fraction of Cu increases beyond a particular value, the intensity of the UV peak decreases while the intensity of the visible peak increases, and the strongest visible emission of a typical ZnO–Cu nanocomposite is over ten times stronger than that of pure Cu. The emission mechanism is discussed. Nonlinear optical response of these samples is studied using nanosecond laser pulses from a tunable laser in the wavelength range of 450–650 nm, which includes the surface plasmon absorption (SPA) band. The nonlinear response is wavelength dependent and switching from reverse saturable absorption (RSA) to saturable absorption (SA) has been observed for Cu nanocolloids as the excitation wavelength changes from the low absorption window region to higher absorption regime near the SPA band. However, ZnO colloids and ZnO–Cu nanocomposites exhibit induced absorption at this wavelength. Such a changeover in the sign of the nonlinearity of ZnO–Cu nanocomposites, with respect to Cu nanocolloids, is related to the interplay of plasmon band bleach and optical limiting mechanisms. The SA again changes back to RSA when we move over to the infrared region. The ZnO–Cu nanocomposites show self-defocusing nonlinearity and good nonlinear absorption behavior. The nonlinear refractive index and the nonlinear absorption increases with increasing Cu volume fraction at 532 nm. The observed nonlinear absorption is explained through two-photon absorption followed by weak free-carrier absorption and interband absorption mechanisms. This study is important in identifying the spectral range and composition over which the nonlinear material acts as a RSA-based optical limiter. ZnO–Cu is a potential nanocomposite material for the light emission and for the development of nonlinear optical devices with a relatively small limiting threshold.

Hyperbranched lutecium phthalocyanines grafted ethylenediamine@graphene oxide with enhanced nonlinear optical properties

2020 ◽  
Vol 24 (08) ◽  
pp. 1038-1046
Author(s):  
Zengduo Cui ◽  
Xin Wang ◽  
Jiale Ding ◽  
Yunhe Zhang ◽  
Zhenhua Jiang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Graphene Oxide ◽  
Organic Solvent ◽  
Nonlinear Optical ◽  
Optical Limiting ◽  
Polymeric Matrix ◽  
Nonlinear Optical Properties ◽  
Photon Absorption ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption

To enhance the nonlinear optical properties of graphene oxide in organic solvent and polymeric matrix, lutecium phthalocyanines (LuPc) and hyperbranched lutecium phthalocyanines (HBLuPc) have been grafted on the surface of graphene oxide, respectively. After the surficial modification, the electron transfer process between phthalocyanines and graphene oxide has been also facilitated, resulting in significant fluorescence quenching. Given the combination of nonlinear scattering, two-photon absorption with reverse saturable absorption and the photo-induced electron or energy transfer from the electron donor (phthalocyanine moiety) to the acceptor (graphene oxide), stronger nonlinear optical properties can be realized based on graphene oxide hybrids compared with graphene oxide and phthalocyanines. Furthermore, graphene oxide hybrid modified by hyperbranched lutecium phthalocyanines exhibits the best optical limiting response and the highest nonlinear extinction coefficient at 532 nm in both organic solvent and polymeric matrix. Interestingly, we also find that it could exhibit better optical limiting properties than those possessed by pure phthalocyanine at 1064 nm.

OPTICAL LIMITING IN TeO2–ZnO GLASS FROM Z-SCAN TECHNIQUE

2011 ◽  
Vol 20 (03) ◽  
pp. 351-356 ◽  
Author(s):  
ROSE LEENA THOMAS ◽  
VASUJA ◽  
MISHA HARI ◽  
B. NITHYAJA ◽  
S. MATHEW ◽  
...  
Keyword(s):  
Optical Properties ◽  
Nonlinear Absorption ◽  
Optical Limiting ◽  
Nonlinear Material ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption ◽  
Absorption Coefficients ◽  
Single Beam ◽  
Optical Limiter

TeO 2– ZnO glasses were prepared by conventional melting procedure, and their optical properties were determined. In the present work, we measured the optical non-linearity of the glass. The measurement was carried out using a single beam z-scan technique given by Sheike Bahe et al. We could observe that the material exhibits reverse saturable absorption, and the effective nonlinear absorption coefficients are numerically evaluated. This study is important in identifying the nonlinear material as a Reverse Saturable Absorption (RSA) based optical limiter.

Nonlinear Absorption and Limiting Behaviour of Monoclinic and Orthorhombic Copper Niobate

2017 ◽  
Vol 865 ◽  
pp. 20-24
Author(s):  
N. Priyadarshani ◽  
T.C. Sabari Girisun
Keyword(s):  
Nonlinear Absorption ◽  
Orthorhombic Phase ◽  
Optical Nonlinearity ◽  
Photon Absorption ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption ◽  
Pore Networks ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Limiting Behaviour

Monoclinic and orthorhombic phase of copper niobate was prepared by simple solid state reaction (700°C, 900°C for 12 hours). Formation of two polymorphic phases of CuNb2O6 was ascertained by XRD and FTIR analysis. FESEM showed the presence of pore networks in both phases. Third-order optical nonlinearity and their limiting behaviour were studied by Z-scan technique using Ti: Sapphire laser (800 nm, 150 fs, 80 MHz). Both phases of copper niobate exhibit reverse saturable absorption. The observed optical limiting action was ascribed due to two-photon absorption process. Monoclinic copper niobate shows almost 100 times stronger nonlinear absorption behaviour than orthorhombic copper niobate due to peculiar distortion of NbO6 octahedra. Monoclinic copper niobate with high two photon absorption coefficient (85x10-10 m/W) and low limiting threshold (0.21 μJ/cm2) can be a better alternate for benchmark optical limiters like carbon nanotubes.

Nonlinear optical properties of polyphthalocyanine porous organic frameworks

2020 ◽  
Vol 44 (36) ◽  
pp. 15345-15349
Author(s):  
Tingfeng Wang ◽  
Tao Sun ◽  
Wei Tang ◽  
Wenbo Huang ◽  
Wenxiang Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Nonlinear Absorption ◽  
Nonlinear Optical ◽  
Optical Limiting ◽  
Nonlinear Optical Properties

sp3-hybridized carbon bridge polyphthalocyanine porous organic frameworks can enhance nonlinear absorption and optical limiting properties.

Light-matter Interaction Under Intense Field Conditions: Nonlinear Optical Properties of Metallic-dielectric Nanostructures

2019 ◽  
Vol 4 (1) ◽  
pp. 51-62
Author(s):  
Enza Fazio ◽  
Luisa D'Urso ◽  
Rosalba Saija ◽  
Saveria Santangelo ◽  
Fortunato Neri
Keyword(s):  
Optical Properties ◽  
Nonlinear Optical ◽  
Nonlinear Refraction ◽  
Optical Limiting ◽  
Nonlinear Optical Properties ◽  
Hybrid Nanostructures ◽  
Field Conditions ◽  
Photon Absorption ◽  
Noble Metal Nanoparticles ◽  
Intense Field

Background: Metallic–dielectric plasmonic nanoparticles have recently aroused great interest in view of many and novel technological applications, based on the interaction between light and matter under intense field conditions, in nonlinear integrated photonics and opto-fluidics, thanks to the possibility of tuning their electronic and optical properties through a fine control of the synthesis parameters and their nanoparticles under a high-power laser, like the one used during z-scan measures. Objective: The goal of this work is the study of nonlinear optical properties (as nonlinear refraction, scattering, two-photon absorption, optical limiting) of colloids synthesized in different liquid media by Pulsed laser ablation in liquids (PLAL), which is a photo-assisted synthesis technique ensuring the formation of stable, contaminant-free colloids directly during the ablation process. Methods: Noble metal nanoparticles, metal oxides hybrid nanostructures and silicon-based nanomaterials, were prepared by nanosecond and picosecond PLAL technique, in different media. The third-order nonlinear optical (NLO) properties have been studied by the use of a single beam z-scan technique with Q-switched frequency doubled Nd:YAG laser (λ=532 nm) at 5 ns pulse. Results: 1) A good stability of the PLAL nanocolloids under a high laser power; 2) the limiting threshold reduction inducted by the Ag-Au nanoparticles, the increase of the NLO absorption coefficient β, the reduction of the transmittance/scattering signal and the presence of a pronounced asymmetry of the peak/valley profile of the metal decorated metal oxide nanomaterials compared to the separately produced components. Conclusion: An intriguing coupling between the nature of the optical limiting response and the nanostructures rearrangement upon intense field conditions, explaining z-scan data by a classical approach able to account for the nanoparticles asymmetry and plasmonic effects, are the main results found.

NONLINEAR ABSORPTION AND OPTICAL LIMITING IN SOLUTIONS OF SOME RARE EARTH SUBSTITUTED PHTHALOCYANINES

2001 ◽  
Vol 10 (01) ◽  
pp. 113-121 ◽  
Author(s):  
K. P. UNNIKRISHNAN ◽  
JAYAN THOMAS ◽  
BINOY PAUL ◽  
ACHAMMA KURIAN ◽  
PRAMOD GOPINATH ◽  
...  
Keyword(s):  
Rare Earth ◽  
Absorption Coefficient ◽  
Nonlinear Absorption ◽  
Optical Limiting ◽  
Photon Absorption ◽  
Open Aperture ◽  
Pulse Excitation ◽  
Two Photon Absorption ◽  
Two Photon ◽  
532 Nm

Effective nonlinear absorption coefficient, β eff , of solutions of some rare earth substituted phthalocyanines (viz: Sm(Pc)2, Eu(Pc)2 and LaPc) was measured using open aperture Z-scan technique under nanosecond pulse excitation at 532 nm. The effect of nonlinear absorption on optical limiting in these samples was also investigated. Both nonlinear absorption and optical limiting phenomena in these samples are attributed to sequential two-photon absorption (STPA) process.

Materials for Reverse Saturable Absorption Optical Limiters

1994 ◽  
Vol 374 ◽  
Author(s):  
James S. Shirk ◽  
Richard G. S. Pong ◽  
Steven R. Flom ◽  
Michael E. Boyle ◽  
Arthur W. Snow
Keyword(s):  
Molecular Structure ◽  
Heavy Metal ◽  
Optical Properties ◽  
Nonlinear Absorption ◽  
Nonlinear Optical ◽  
Optical Systems ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption ◽  
Spectral Window ◽  
Optical Limiters

AbstractSystematic studies of the nonlinear optical properties of metallo-organic materials have led to the development of promising new phthalocyanine materials for optical limiting. Several heavy metal substituted phthalocyanines exhibit a strong nonlinear absorption that is useful for optical limiters in the visible. In fast optical systems, other mechanisms, such as the thermal refraction, contribute to the limiting. The spectral window for limiting can by modified by altering the molecular structure.

scholarly journals Broadband Visible Nonlinear Absorption and Ultrafast Dynamics of the Ti3C2 Nanosheet

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2544
Author(s):  
Yabin Shao ◽  
Chen Chen ◽  
Qing He ◽  
Wenzhi Wu ◽  
Chensha Li ◽  
...  
Keyword(s):  
Nonlinear Absorption ◽  
Transient Absorption ◽  
Laser Energy ◽  
Visible Region ◽  
Photon Absorption ◽  
Saturable Absorption ◽  
Reverse Saturable Absorption ◽  
Ultrafast Dynamics ◽  
Fast Decay ◽  
Broadband Absorption

The Ti3C2 nanosheet, as a new two-dimensional (2D) group, has been found to have attractive characteristics as material for electromagnetic shielding and energy storage. In this study, the nonlinear broadband absorption and ultrafast dynamics of the Ti3C2 nanosheet were investigated using nanosecond open-aperture Z-scan and transient absorption techniques. The mechanism of two-photon absorption (TPA) was revealed in the visible region (475–700 nm). At lower incident energies, nonlinear absorption could not happen. When the laser energy increased to 0.64 GW/cm2, electrons in the valence band could absorb two photons and jump to the conduction band, with TPA occurring, which meant that the sample exhibited reverse saturable absorption (RSA). In addition, when transient absorption was used to investigate the ultrafast carrier dynamics of the sample, it demonstrated that the relaxation contains a fast decay component and a slow one, which are obtained from electron–phonon and phonon–phonon interactions, respectively. Moreover, with the increasing pump fluence, the fast decay lifetime τ1 increased from 3.9 to 4.5 ps, and the slow one τ2 increased from 11.1 to 13.2 ps. These results show that the Ti3C2 nanosheet has potential applications in broadband optical limiters.

Third-order optical nonlinearity of DSR13/THF solutions under CW He–Ne laser irradiation using Z-scan method

2021 ◽  
pp. 1-7
Author(s):  
Bassam Abbas ◽  
Mohammad Alshikh Khalil
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Nonlinear Absorption ◽  
Nonlinear Refractive Index ◽  
Nonlinear Optical ◽  
Nonlinear Optical Properties ◽  
Photon Absorption ◽  
Third Order ◽  
The Third ◽  
Order Susceptibility

The Z-scan technique was employed to explore the third-order nonlinear optical properties of disperse red 13 organic chromophore solutions in tetrahydrofuran. A continuous-wave He–Ne laser (632.8 nm) was used as a source of irradiation. The nonlinear absorption and nonlinear refractive index coefficients of this dye were investigated. The results showed that this dye has a good nonlinear response with its real and imaginary quantities of third-order susceptibility. The solutions showed negative nonlinear refraction. The best obtained value of the third-order susceptibility was 6.37 × 10–3 esu at a dye concentration of 3.15 × 10–4 mol/L. Moreover, the nonlinear optical properties were enhanced with higher dye concentrations, and an elevated trend in nonlinear absorption and nonlinear refractive index coefficients was observed. Also, it was found that the reverse saturable absorption was the main mechanism responsible for the two-photon absorption effect in DSR13/THF samples.

Sign in / Sign up

Export Citation Format

Share Document