Nonlinear Optical Applications Research Articles

Dynamics of novel soliton and periodic solutions to the coupled fractional nonlinear model

This study secures the soliton solutions of the (2+1)-dimensional Davey–Stewartson equation (DSE) incorporating the properties of the truncated M-fractional derivative. The DSE and its coupling with other systems have extensive applications in many fields, including physics, applied mathematics, engineering, hydrodynamics, plasma physics, and nonlinear optics. Various solutions, such as dark, singular, bright-dark, bright, complex, and combined solitons, are derived. In addition, exponential, periodic, and hyperbolic solutions are also generated. The newly designed integration method, known as the modified Sardar subequation method (MSSEM), has been applied in this study for extracting the solutions. The approach is efficient in explaining fractional nonlinear partial differential equations (FNLPDEs) by confirming pre-existing solutions and producing new ones. Furthermore, we plot the density, 2D, and 3D graphs with the associated parameter values to visualize the solutions. The outcomes of this work indicate the effectiveness of the method utilized to improve nonlinear dynamical behavior. We anticipate that our work will be helpful for a large number of engineering models and other related problems.

Tamm plasmon-induced impressive optical nonlinearity of silver@graphite core–shell nanostructures

Abstract We demonstrate the enhancement in the optical nonlinearity of materials when incorporated within a Tamm plasmon cavity (TPC). This study quantitatively investigates the enhanced nonlinear optical effects exhibited by silver@graphite (Ag@C) core–shell nanostructures integrated within a Tamm plasmon cavity. The Ag@C core–shell nanostructures were synthesized by laser ablation. The transmittance characteristics of the TPC are well-matched with those of the simulated spectra. Nonlinear optical studies, conducted using the open aperture Z-scan technique, demonstrated reverse saturable absorption (RSA) behavior in the Tamm plasmon cavity structure, and a profound enhancement in nonlinear absorption compared to that of the bare material film was also observed. The optical limiting threshold value was found to be 2.5 J/cm2 which is indeed a better value when compared to the reported values. Computational simulations illustrated a significantly intensified electric field within the Tamm plasmon cavity, suggesting the creation of enhanced photonic states leading to increased light–matter interactions. These findings underscore the potential of Ag@C core–shell nanostructures within Tamm plasmon cavities for advancing nonlinear optical devices and applications.

Efficient Poling‐Free Wavelength Conversion in Thin Film Lithium Niobate Harnessing Bound States in the Continuum

AbstractOver the past two decades, there has been a surge of interest in photonic integrated circuits (PICs) to enable low‐cost industrial mass manufacture of miniaturized optical systems while simultaneously improving performance and energy efficiency following the trajectory of electronics and large‐scale integration. An essential characteristic of any PIC lies in the ability of waveguides to efficiently confine light. The phenomenon of bound states in the continuum (BIC) shows promise in achieving confinement of light for modes that otherwise would suffer from high leakage losses, which can occur in many PIC platforms. In this contribution, the usefulness of operating near a BIC to achieve efficient second harmonic generation of ≈300% W−1 cm−2 in Silicon Nitride (SiN) loaded lithium niobate on insulator (LNOI) waveguides without needing to either pole or etch the lithium niobate is experimentally demonstrated. The guided fundamental mode is phase matched at the telecom wavelength to a higher order mode at the second harmonic wavelength that is engineered as a bound state in the continuum to mitigate leakage losses. This demonstrates the promise of using BIC in weakly confining waveguides for nonlinear optical applications all while avoiding the poling process by engineering waveguide geometry.

Impact of doping with organic dopants and mixed doping with alkali metals and organic dopants on the absorption, electronic, optoelectronic, thermodynamic and nonlinear optical properties of dibenzo[b,def]chrysene in gaseous media: DFT and TD-DFT studies.

In this study, we evaluate the geometrical, absorption, optoelectronic, electronic, nonlinear optical (NLO) and thermodynamic properties of dibenzo[b,def]chrysene molecule derivatives by means of DFT and TD-DFT simulations. In view of the aim of producing new high-performance materials for non-linear optics (NLO) by doping test, two types of doping were used. We obtained six derivatives by doping with organic dopants (Nitro, amide and ticyanoethenyl) and mixed alkali metal (potassium) and organic dopants. Doping with organic dopants produced molecules A, B and C, respectively when substituting one hydrogen with nitro (NO2), amide (CONH2) and tricyanoethenyl (C5N3) groups, while mixed doping involved considering A, B and C and then substituting two hydrogens with two potassiums to obtain compounds D, E and F respectively. The negative values of the various interaction energies calculated for all the doped molecules show that they are all stable, but also that molecules C and F are the most stable in the case of both dopings. The gap energies calculated at the B3LYP level of theory are all below 3eV, which means that all the molecules obtained are semiconductors. Better still, compounds C and F, with gap energies of 1.852eV and 1.204eV, respectively, corresponding to decreases of 35.67% and 58.18% in gap energy compared with the pristine molecule, are more reactive than the other doped molecules. Mixed doping is therefore a highly effective way of narrowing the energy gap and boosting the semiconducting character and reactivity of organic materials. Optoelectronic properties have also been improved, with refractive index values higher than those of the reference material, glass. This shows that our compounds could be used under very high electric field conditions of the order of 4.164 109V.m-1 for C and 7.410 109V.m-1 for F the highest values at the B3LYP level of theory. The maximum first-order hyperpolarizability values for both types of doping are obtained at the CAM-B3LYP level of theory by C: 10-30esu and by F: 10-30esu, and second-order values are also given by these same compounds. These values are higher than the reference value, which is urea, making our compounds potential candidates for high-performance NLO applications. In dynamic mode and at a frequency of 1064nm, at the CAM-B3LYP level of theory, the highest dynamic hyperpolarizability coefficients were obtained by C and F. Hyper-Rayleigh scattering , coefficients of the electro-optical Pockel effect (EOPE), EFISHG, third-order NLO-response degree four-wave mixing , quadratic nonlinear refractive index n2 were also calculated. The maximum values of n2 are obtained by C (6.13 10-20 m2/W) and F (6.60 10-20 m2/W), these values are 2.24 times higher than that of fused silica which is the reference for degenerate four-wave mixing so our molecules could also have applications in optoelectronics as wavelength converters, optical pulse modulators and optical switches. Using the DFT method, we were able to determine the optimized and stable electronic structures of doped dibenzo[b,def]chrysene derivatives in the gas phase. We limited ourselves to using the proven B3LYP and CAMB3LYP levels of theory for calculating electronic properties, and non-linear optics with the 6-311G + + (d,p) basis set, which is a large basis set frequently used for these types of compound. Gaussian 09 software was used to run our calculations, and Gauss View 6.0.16 was used to visualize the output files. TD-DFT was also used to determine absorption properties at the B3LYP level of theory, using the same basis set.

A comprehensive investigation of the synthesis, spectral, DFT, and optical properties of a novel oxadiazolyl-pyrano[3,2-c]quinoline for photosensor applications

The condensation reaction of pyranoquinoline-3-carbaoxldehyde 1 with benzohydraide afforded hydrazone 2 which upon oxidative cyclization yielded 6-ethyl-4‑hydroxy-3-(5-phenyl-1,3,4-oxadiazol-2-yl)-2H-pyrano[3,2-c]quinoline-2,5(6H)‑dione (EHPOPQ, 3). The DFT and B3LYP/6–311++G(d,p) basis set were used to compute the optimized molecular geometry. The global reactivity descriptors were examined and showed that hydrazone 2 exhibited high softness while aldehyde 1 had more electronegativity and high global electrophilicity. Subsequently, the reactive sites of the present compounds were located by tracing the MEP map. The GIAO method was used to calculate the 1H and 13C NMR. The current comprehensive investigation of the novel (EHPOPQ) reveals its significant potential for applications in nonlinear optics (NLO) and photovoltaics. Through high-level computational methods, EHPOPQ has an exceptionally high first hyperpolarizability (βtot) of 950 × 10−30 esu, which is substantially higher than that of the conventional NLO material urea. This high βtot value suggests that EHPOPQ could dramatically enhance the efficiency and performance of NLO devices such as frequency converters and optical modulators. In parallel, the detailed spectroscopic analysis of EHPOPQ's optical properties provided critical insights for photovoltaic applications. The optical band gap was measured to be 3.07 eV, indicating a direct band gap transition suitable for efficient light harvesting in solar cells. Additionally, dispersion parameters were carefully analyzed, which are essential for understanding the interaction of light with the material. The experimental characterization of EHPOPQ-based photovoltaic devices showed promising results. Current-voltage (J-V) measurements under varying illumination intensities revealed significant enhancements in the device's short-circuit current (from 1.2 µA to 4.3 µA) and open-circuit voltage (from 0.25 V to 0.47 V) as light intensity increased. These findings demonstrate the material's heightened photoresponsivity and suggest its potential as an efficient light conversion material for solar energy applications. These specific findings underline the importance of EHPOPQ in advancing both NLO and photovoltaic technologies, offering a pathway to more efficient and effective devices.

Phase sensitive slow light in semiconductor quantum dots

This article presents a theoretical investigation of phase-controlled propagation of slow light under an electromagnetically induced transparency window in a multilayered one-dimensional photonic crystal with semiconductor quantum dot nanostructures as defects. To achieve the electromagnetically induced transparency window, a setup utilizes a faint probe laser pulse alongside two powerful control laser beams arranged in a closed-loop cascade configuration. In this arrangement, a significant Kerr nonlinearity, approximately on the scale of ∼10−13m2/V2, is discerned within the quantum dot nanostructures at a probe wavelength of 1.55 μm. It is observed that both the amplitude and the phase relationship of the control Rabi frequencies play crucial roles in governing the dynamics of the group velocity of the probe field in the quantum dot nanostructures. Under the regime of electromagnetically induced transparency, the group velocity of the probe field is significantly reduced, approximately by a factor of 103 times as compared to the light speed in free space. These findings hold promise for potential applications in nonlinear optics.

Insights into the optoelectronic and thermoelectric properties of defect chalcopyrites XAl2Se4 (X = Zn, Cd, and Hg): A density functional theory approach

In the current study, we employed the full-potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) approach within the density functional theory (DFT) to investigate the physical properties of Defect Chalcopyrites XAl2Se4 (X = Zn, Cd, and Hg). Calculations yield precise structural and electronic parameters in good agreement with experimental data, revealing all three compounds as direct wide-bandgap semiconductors. The modified Becke-Johan potential (TB-mBJ) method accurately estimates energy gaps, which increase with decreasing lattice constants. The calculated values are 3.34 eV, 3.12 eV, and 2.30 eV for ZnAl2Se4, CdAl2Se4, and HgAl2Se4, respectively. The optical properties, including dielectric function and absorption coefficient, indicate potential applications in visible and ultraviolet optoelectronic devices. The high anisotropy of these materials further enhances their suitability for a range of linear and nonlinear optical applications. Moreover, ZnAl2Se4 exhibits the highest Seebeck coefficient at room temperature. The positive Seebeck coefficient confirmed the p-type behavior of the studied compounds. The highest observed power factor demonstrates optimal thermoelectric performance for these materials. High electrical conductivity values suggest their suitability as effective electrical conductors, especially at elevated temperatures. This study encourages further research into defect chalcopyrites for applications in optoelectronics and thermoelectric energy conversion.

Growth and characterization of organic 4-chloroaniline single crystals for nonlinear optical applications

Growth and characterization of organic 4-chloroaniline single crystals for nonlinear optical applications

Styrene monomer as potential material for design of new optoelectronic and nonlinear optical polymers: density functional theory study.

Using density functional theory, we have studied the intrinsic properties of styrene. First, we determine the optimized structures, structural parameters and thermodynamic properties to make our simulations more realistic to experimental results and check the stability. Second, we investigate optoelectronic, electronic and global descriptors, transport properties of holes and electrons, natural bond orbital analysis, absorption and fluorescence properties. Finally, we study nonlinear optical (NLO) properties: first- and second-order hyperpolarizability, second and third-order optical susceptibilities, hyper-Rayleigh scattering hyperpolarizability, electro-optical Pockel effect, direct current Kerr effects and quadratic refractive index. The bandgap energy E g = 5.146 eV and dielectric constant show that styrene is a good insulator with an average electric field value of 4.43 × 108 Vm-1. Thermodynamic findings show that our molecule is thermodynamically and chemically stable. Electron and hole reorganization energies of 0.393 and 0.295 eV, respectively, show that styrene is more favourable to hole transport than electron transport. Styrene is transparent with linear refractive index n = 1.750 and quadratic n 2 = 1.748 × 10-20 m2 W-1. At the NLO, styrene has a non-zero value of which confirms the existence of first-order NLO activity. Globally the study shows that the styrene monomer is suitable for the architecture design of new polymer materials for NLO applications and optoelectronic by functionalization.

Deciphering the impact of superalkali metals [M3O (M = Li, Na, K)] doping on sulflower for enhanced NLO responses with efficient energetic offsets: A density functional theory perspective

With the motive to enhance nonlinear optical (NLO) materials, the geometries, stabilities, and NLO responses of superalkali metals [M3O (M = Li, Na, K)] doped sulflower (Octathio[8]circulene) is explored using DFT simulations and computational characterization. Binding energies from −6.07 to −29.27 kcalmol-1 demonstrate the thermal stability of M3O@sf isomers. The E(H-L) gap was reduced to 84.84 % upon M3O@sf doping. Superalkali metal doping of sulflower substantially improves the first hyperpolarizability (βo) value of complexes. A comparative study illustrates that the hyperpolarizability of the superalkalis has a monotonic relationship with the nature of metal atoms. Among all the studied isomers, K3O@sf-III has the highest βo value of 3.2×107 au. The significant charge transfer (determined by NBO), decrease in excitation energy values, increase in dipole and polarizability values justify that there has been a significant increase in the βo values. This work introduces an opportunity to develop thermally stable NLO materials which can potentially be used for high-performance NLO applications.

Acoustic shock-pulse-induced tunable structural and optical properties of L-Histidine maleate single crystals for photonic applications

In this paper, a single crystal of L-histidine maleate (LHM) was grown using a slow evaporation solution process. A tabletop shock tube is used to generate shock pulses. Shock waves' impact on the optical and structural characteristics of the LHM single crystal was studied for 0, 1, 2, and 3 shock pulses with a Mach number of 1.7. Analytical methods such as Powder X-ray diffraction, Raman, UV–visible spectroscopy, and optical microscopic techniques were utilized to get a deep understanding of the shock pulse impact of the title crystals. The crystalline nature is observed to be increased at the third shocked condition, as shown by the Raman and PXRD data. The UV-visible studies infer the enhancement of the crystal's optical-transmittance at 3rd shocked condition. It is to be noted that, the difference between optical transmittance at the impact of 2nd and 3rd shock is almost 30 %. It is evident from the data that, the applied shock waves are capable of tuning the local crystalline perfection and the optical transmittance of the test crystals. The shock wave induced higher crystalline perfection and optical transmittance LHM crystal is strongly suggested to the non-linear optical applications.

Stacking Faults Enabled Second Harmonic Generation in Centrosymmetric van der Waals RhI3.

Second harmonic generation (SHG) in van der Waals (vdW) materials has garnered significant attention due to its potential for integrated nonlinear optical and optoelectronic applications. Stacking faults in vdW materials are a typical kind of planar defect that introduces a degree of freedom to modulate the crystal symmetry and resultant SHG response. However, the physical origin and tunability of stacking-fault-governed SHG in vdW materials remain unclear. Here, taking the intrinsically centrosymmetric vdW RhI3 as an example, we theoretically reveal the origin of stacking-fault-governed SHG response, where the SHG response comes from the energetically favorable AC̅ stacking fault of which the electrical transitions along the high-symmetry paths Γ-M and Γ-K in the Brillion zone play the dominant role at 810 nm. Such a stacking-fault-governed SHG response is further confirmed via structural characterizations and SHG measurements. Furthermore, by applying hydrostatic pressure on RhI3, the correlation between structural evolution and SHG response is revealed with SHG enhancement up to 6.9 times, where the decreased electronic transition energies and higher momentum matrix elements due to the stronger interlayer interactions upon compression magnify the SHG susceptibility. This study develops a promising foundation for nonlinear nano-optics applications through the strategic design of stacking faults.

Exploring structural and optical properties of shock wave-loaded polycrystalline picric acid: implications for molecular engineering applications

Abstract The shock wave impact on hydrogen-bonded organic materials’ structural properties and their responses with respect to their associated functional properties is one of the most prevalent research topics because of the possible emergence of unusual functional properties. Presently, we intend to examine the structural response of the poly-crystalline picric acid samples under shocked conditions. The crystallographic structural responses and the linear optical properties of the test samples have been examined by powder XRD analysis, ultra-violet diffused reflectance spectroscopy (UV-DRS) and Raman spectroscopy, respectively. Under shocked conditions, a considerable modification in the diffraction peak positions and their intensity changes could be witnessed. Notably, linear optical transmittance profiles show remarkable changes according to the number of applied shock pulses, such that the 150-shocked sample has the highest optical transmittance of 53.9 % at 350 nm, whereas the control sample has an optical transmittance of 6.6 %. The Raman spectrum shows the vibrational groups of material that are stable in shocked conditions with similar intensity changes. Based on the obtained XRD, UV-DRS and Raman results, shock wave-induced picric acid samples have remarkably improved characteristics of optical transmittance, which is highly favorable for non-linear optical applications.

New push–pull ladder-type chromophores with large hyperpolarizability for nonlinear optical application

New push–pull ladder-type chromophores with large hyperpolarizability for nonlinear optical application

Effect of partial substitution of K2O by MgO on the structure, and thermal, physical, optical properties and crystallization behaviour of K2O–MgO–B2O3–P2O5 glasses

In this work, a series of K2O–MgO–B2O3–P2O5 (KMBP) glasses were prepared by the melt-quenching method and the glass-ceramics were prepared by the one-step heat treatment. The thermal, structural, physical and optical properties, as well as the crystallization behaviour of the KMBP system, were investigated in detail using characterization techniques such as DSC, XRD, SEM, FTIR, transmittance spectroscopy and microhardness. As indicated by DSC, the thermostability and glass-forming ability were gradually enhanced through the partial substitution of K2O by MgO. XRD showed that the main crystalline phases of the glass-ceramics (GC) were gradually converted from the P–Mg–K–O based crystalline phases to the P–Mg–O based and the P–Al–O based crystalline phases. The SEM results indicated that tiny grain-like crystals were successfully precipitated from the parent glasses after heat treatment. The deconvoluted FTIR spectra results showed a gradual conversion of the [BO3] and [PO3] units towards the [BO4] and [PO4] units with the increase of the MgO contents. The increase in the degree of glass network polymerization was the essential reason for the increment in the microhardness of the parent glasses. The microhardness of GC featured a trend concordant with the crystallinity of the crystalline phases. The values of metallization criteria (MC) between 0.34 and 0.45, as well as the higher values of third-order nonlinear polarizability (χ(3)) and nonlinear refractive index (nnl) are indicative of the good suitability of the KMBP glasses for the nonlinear optical applications.

Theoretical investigation on the second order nonlinear optical properties of heptagon bridged bi-porphyrin derivatives

Porphyrins and their derivatives have drawn extensive attention as promising nonlinear optical (NLO) materials especially for biological applications owing to its large aromatic conjugation and special biological activity and compatibility. However, it is still critical to strategically design porphyrin derivatives materials with high performance in second order NLO applications and disclose the structure property correlation. In the present work, a series of dual-metallic-porphyrin derivatives are designed by incorporating a heptagon between two porphyrins with further addition of heteroatoms and metals. The doping of B and N along the dipole direction induces large static first hyperpolarizability, and strong charge transfer occurs with further introduction of Mg, thus ultimately achieving excellent second order NLO properties including strong sum frequency generation and difference frequency generations under external fields. The doping of heteroatoms and metals synergistically tunes the electronic structure of porphyrin-based derivatives and brings about high performance in biological nonlinear optics.

Modification in the Optical and Dielectric Characteristics of Poly (Vinyl Alcohol)/Carboxymethyl Cellulose Blended Polymers Doped with Two Phases Nanocomposites for Application in Optoelectronic and Energy Storage Devices

Nanocomposite films comprised of poly (vinyl alcohol) (PVA) and carboxymethylcellulose (CMC) were fabricated via a solution casting procedure, with the incorporation of (1-x)CuCo2O4/xZnMn2O4. Our research described here was aimed to explore the impact of the (1-x)CuCo2O4/xZnMn2O4 on the structural, optical and electrical features of the PVA/CMC blended polymer, using various techniques. The different phases formed (CuCo2 O4 and/or ZnMn2O4) in (1-x) CuCo2O4/x ZnMn2O4 filler samples were identified applying Rietveld refinement analysis. The structures and morphologies of the PVA/CMC/(1-x)CuCo2O4/xZnMn2O4 blend composites were determined using X-ray diffraction and scanning electron microscopy techniques. Their various linear and nonlinear optical parameters were examined using the diffused reflectance technique. The blended polymer composite with x = 0.1 displayed the highest absorbance. The transmittance of the PVA/CMC blend declined from 91 to 69% when it was loaded with a nanocomposite containing 10% ZnMn2O4. The optical band gaps of the doped blend composites had their lowest values, 5.45 eV for direct transition and (4.83, 2.99, 2.31) eV for the indirect transition, as the blend was loaded with the fillers containing 10 and 15% ZnMn2O4. The study also explored the influence of the (1-x)CuCo2O4/x ZnMn2O4 on the fluorescence spectra and chromaticity diagram of the PVA/CMC blend. The effect of the filler on the complex dielectric constant, complex electric modulus, ac conductivity and electrical storage energy of the host blend was examined. The obtained characteristics imply potential utility of the doped blends in photocatalytic, UV-blocking, UV-filtering, optoelectronic, electrical storage, nonlinear optical and photonic applications.

Influence of procion red dye doping on the structural, dielectric and optical properties of diglycine-phthalic acid single crystals for nonlinear optical applications

Influence of procion red dye doping on the structural, dielectric and optical properties of diglycine-phthalic acid single crystals for nonlinear optical applications

Growth and characterization of organic p-nitroacetophenone single crystals for nonlinear optical applications

Growth and characterization of organic p-nitroacetophenone single crystals for nonlinear optical applications

V2O5/Ti3C2 MXene-Based Solid-State Passively Mode-Locked Tm:YAP laser at 2 μm

In the present work, V2O5/Ti3C2 MXene hybrid nanomaterials were successfully synthesized. The morphology and structure of the prepared V2O5/Ti3C2 MXene were investigated, and the results showed excellent bonding and strong interaction between Ti3C2 MXene and V2O5 nanoparticles. The nonlinear absorption properties of V2O5/Ti3C2 MXene nanocomposites at 2 μm have been investigated using power transfer techniques, and the large modulation depth of the material gives it potential for applications in nonlinear optics. As a result, a 2 μm solid-state mode-locked pulsed laser with V2O5/Ti3C2 MXene as a saturable absorber has been realized for the first time, generating a pulsed laser output as short as 657 ps, which corresponds to an average output power of 0.67 W. The results show that the synthesized V2O5/Ti3C2 MXene hybrid nanomaterials, which have a large optical nonlinearity, can be applied to generating an ultrashort 2 μm pulsed laser.