Application Of Laser Technology Research Articles

Design of miniaturized wide band-pass plasmonic filters in MIM waveguides with tailored spectral filtering

This paper reports the design and numerical results of three new extremely compact and efficient flat-top band-pass plasmonic filters operating in the near-infrared region. The proposed structures are realized in metal–insulator-metal plasmonic waveguides based on stub, tilted T-junction and right-angle trapezoid configurations. A built-in parameterized genetic algorithm is applied to maximize the transmission efficiency, while at the same time contributing to shrinking down the size of the device structures. It is shown that the tunability of the optical filters can be realized by modulating their structural parameters to gain control over the band-pass filtering wavelengths. Numerical calculations are conducted based on the finite element method of CST Microwave Studio and demonstrate that the suggested ultra-compact plasmonic waveguide filters offer wide bandwidths of more than 270 nm, 424 nm, and 289 nm, with transmission efficiencies of higher than 80%, 74.2%, and 74.3%, respectively. The sizes of the proposed wavelength filters are 490 nm × 575 nm, 350 nm × 180 nm, and 420 nm × 150 nm, respectively, which make them attractive candidates for applications in high density photonic integrated circuits (PICs). As a result, because of the promising characteristics of the proposed topologies such as their high efficiency, compact size, tunability, and simple structure they may find applications in on-chip integration, laser technology, and multi-photon fluorescence.

A2Pb3[H2N(CH2COO)2]3Cl5 (A = K, Rb): Porous Crystals Constructed on [Pb3Cl5O6] Clusters with Comprehensive Nonlinear Optical Performance

AbstractNonlinear optical (NLO) crystals that can extend the frequency range of coherent light have significant applications in laser technology, semiconductor manufacturing, and lithography. Herein, two interesting NLO crystals, A2Pb3[H2N(CH2COO)2]3Cl5 (A = K, Rb), are rationally obtained. Their porous structures are constructed on [Pb3Cl5O6] clusters that possess large hyperpolarizability and polarizability anisotropy, and are arranged in a parallel manner. Remarkably, A2Pb3[H2N(CH2COO)2]3Cl5 (A = K, Rb) exhibits comprehensive NLO performance, including strong phase‐matching second‐harmonic generation (SHG) response, the widest bandgap among lead oxychloride NLO crystals, larger laser damage threshold than 127 MW cm−2, suitable birefringence of 0.11@1064 nm, high thermal stability, non‐deliquescence, as well as facile crystal growth. Theoretical calculations and structural analysis demonstrate that their strong SHG response is predominantly originated from the [Pb3Cl5O6] cluster. This study will provide a unique method for the discovery of new interesting NLO crystals in future.

Femtosecond Laser Microfabrication of Artificial Compound Eyes

Over millions of years of evolution, arthropods have intricately developed and fine-tuned their highly sophisticated compound eye visual systems, serving as a valuable source of inspiration for human emulation and tracking. Femtosecond laser processing technology has attracted attention for its excellent precision, programmable design capabilities, and advanced three-dimensional processing characteristics, especially in the production of artificial bionic compound eye structures, showing unparalleled advantages. This comprehensive review initiates with a succinct introduction to the operational principles of biological compound eyes, providing essential context for the design of biomimetic counterparts. It subsequently offers a concise overview of crucial manufacturing methods for biomimetic compound eye structures. In addition, the application of femtosecond laser technology in the production of biomimetic compound eyes is also briefly introduced. The review concludes by highlighting the current challenges and presenting a forward-looking perspective on the future of this evolving field.

Principal Analysis and Application of Laser Technology in Integrated Circuits

Since the constant development of science and technology and the popularization of electronic devices, integrated circuits are also developing in the direction of large scale and high precision. This requires the processing of integrated circuits to be constantly refined. This also prompted the laser technology has become an important processing technology in the manufacturing process of large-scale integrated circuits. Laser processing technology is a non-contact processing, its beam diameter is small, high-energy density, high productivity, stable and reliable processing quality. This paper for the laser welding, laser direct writing, laser detection and laser cleaning overview of the four-laser technology in the application of large-scale integrated circuits. And the working principle, type and process characteristics of these laser technologies are discussed. The development of laser technology has also limited the production of large-scale integrated circuits in some aspects. With the semiconductor laser, excimer laser process continues to mature, laser technology in integrated circuits will continue to expand the scope of application and break through the obstacles.

Study on the application of laser technology in the restoring and transformation of PbS on painted cultural relics

Lead white darkening is a common disease in all kinds of painted cultural relics. In this study, a combination of laser and photodynamic technology was used to achieve controlled restoration of lead sulfide at the lead darkening site on the painted layer of cultural relics by laser catalysis with porphyrin to produce singlet oxygen. The chromatic change, micromorphology and chemical composition were systematically studied for a simulated sample with the lead darkening part of the painted layer. The results show that laser catalytic treatment can repair the color darkening that occurs by the PbS formation, while no obvious changes to the pore and microparticle structure of the painted layer and the base. In this study, the pollutant of lead sulfide was proved to be converted into lead sulfate by oxidation, and then was converted to lead white by precipitation, which was the original composition of the pigment. It is also found that the laser catalytic treatment method can effectively avoid basic layer damages of cultural relics, especially for the papers, the silks and other organic materials. This technology not only provides a new approach for the restoration and transformation of PbS on painted cultural relics, but also makes available new applications for the laser and photodynamic technology in the field of cultural relics protection.

Laser-Driven Rapid Synthesis of Metal-Organic Frameworks and Investigation of UV-NIR Optical Absorption, Luminescence, Photocatalytic Degradation, and Gas and Ion Adsorption Properties.

In this study, we designed a platform based on a laser-driven approach for fast, efficient, and controllable MOF synthesis. The laser irradiation method was performed for the first time to synthesize Zn-based MOFs in record production time (approximately one hour) compared to all known MOF production methods with comparable morphology. In addition to well-known structural properties, we revealed that the obtained ZnMOFs have a novel optical response, including photoluminescence behavior in the visible range with nanosecond relaxation time, which is also supported by first-principles calculations. Additionally, photocatalytic degradation of methylene blue with ZnMOF was achieved, degrading the 10 ppm methylene blue (MB) solution 83% during 1 min of irradiation time. The application of laser technology can inspire the development of a novel and competent platform for a fast MOF fabrication process and extend the possible applications of MOFs to miniaturized optoelectronic and photonic devices.

Principle of Free-electron Laser and Applications in Medical Research and Lithography

In recent years, as a breakthrough light source technology, free-electron laser (FEL) has the unique advantage of producing coherent radiation with high brightness, high energy, good directivity and excellent monochromaticity. With this in mind, this study will systematical discuss the historical development of FEL technology, from Einstein's laser theory to Dr. Maiman's first commercial laser, as well as the birth and evolution of FEL. To be specific, the basic principles and construction of FEL technology will be discussed in detail, including key components such as electron sources, electron accelerators, and oscillators. The application of free electron laser (FEL) technology in medicine and lithography will also be demonstrated in this paper. According to the analysis, the current limitations of the state-of-art facilities as well as the future development trends and improvements for FEL system will be clarified based on the evaluations. Overall, these results shed light on guiding further exploration of FEL techniques.

Femtosecond pulsed laser technology and applications

This paper describes femtosecond pulsed laser technology and related applications. The focus is on two core femtosecond pulsed laser technologies: femtosecond pulsed laser generation and amplification. In the generation of femtosecond pulsed lasers, mode-locking techniques, Kerr-lens mode-locking, and semiconductor saturable absorber mirrors are presented; in the amplification of femtosecond pulsed lasers, chirped-pulse amplification and coherent synthesis techniques are presented. This paper analyses the applications of femtosecond pulsed lasers in both the biomedical and manufacturing sectors and gives the development trends as well as the challenges of femtosecond laser technology. Femtosecond lasers are now used in a wide range of applications. Femtosecond pulsed lasers will develop in the directions of high power, miniaturisation, intelligence and precision. Laser tweezers will become the new direction of development in the future.

Mid-infrared second-harmonic generation and its red-shift signal induced by cross-phase modulation in an AsSe2 soft glass microstructured optical fiber

In this study, we investigate an AsSe2 soft glass microstructured optical fiber (MOF) featuring a hexagonal arrangement of six holes. The MOF is subjected to femtosecond laser pumping, employing a pump wavelength range spanning from 3950 nm to 4100 nm. Our experimental results reveal an intriguing outcome: a tunable mid-infrared second-harmonic generation (SHG) effect is observed, yielding a wavelength range of ∼ 1980 nm to ∼ 2203 nm. The maximum conversion efficiency is achieved at 4100 nm with a power of 130 mW, which can be up to 9.2E-5. The observed SHG is primarily due to the surface nonlinearity polarization at the core-cladding interface. Additionally, we increase the additional degrees of freedom of the SH signal by strong third-order nonlinearity, and demonstrate that strong self-phase modulation (SPM) of pump and cross-phase modulation (XPM) of SH signal help broaden the SH signal by means of generating new wavelength lobes. To the best of our knowledge, this is the first time that strong XPM-based SH signal is observed in an optical fiber in the mid-infrared wavelength region. The realized strong second-order and third-order nonlinearity might expand the fundamental physical mechanism of SHG in optical fiber especially in mid-infrared region, which would have important applications in telecommunications, laser technology, and quantum photonics.

Picosecond lasers in cosmetic dermatology: where are we now? An overview of types and indications.

Q-switched lasers have undeniably revolutionized the field of laser dermatology since four decades ago. Just as the first-generation laser emits its photonic signal in a few nanoseconds, the picosecond laser delivers pulse widths of at least ten times shorter. These devices offer a powerful tool for treating a wide range of skin conditions with a minimal downtime for visible improvement. For the current study, a literature research was performed on the dermatological applications of picosecond laser. The literature searched on this topic between 1999 and 2023 accessible through various platforms produce a result of 62 articles. The included studies have discussed the application of picosecond laser technology in tattoo removal, treatment of epidermal and dermal pigmentation, and collagen remodeling. After sifting the data from the articles into tables, the results were discussed in detail. The study shows a lot of evidence towards the efficacy of picosecond laser, yet it draws attention to its downsides.

First-principles study on the electronic structures and optical properties of Mg-doped KDP crystal

First-principles method was employed to study the defect formation energy, electronic structure, and optical properties of Potassium Dihydrogen Phosphate (KDP) crystals doped with Mg in both paraelectric phase (PE-KDP) and ferroelectric phase (FE-KDP). Additionally, we employed the HSE hybrid density functional to address the issue of “band gap” and utilized the finite size correction-finite volume (FNV) method to rectify defect formation energies. Due to hybridization of Mg-3s orbitals with O-2p orbitals, a defect energy level is created at the conduction band minimum (CBM), resulting in the band gap of Mg-doped KDP crystals being smaller than that of perfect crystals. Moreover, the incorporation of Mg leads to significant lattice distortions and alters bond lengths, particularly the O–Mg bonds, which are stretched by 0.65–0.77 Å. The optical spectra also have been obtained under the consideration of electron-phonon coupling. The absorption peak locates at 4.37 eV (284 nm) in PE-KDP. The absorption peak locates at 4.66 eV (266 nm) in FE-KDP. Moreover, the significant Stokes shifts (3.67 eV and 2.9 eV) observed in Mg-doped KDP crystals were attributed to lattice relaxation energy and distortions induced by the substitution. The calculated results indicate that the quality of the KDP crystals may be reduce by introducing Mg-impurities. The work provides valuable insights into the optical characteristics of Mg-doped KDP crystals and their potential applications in laser technology.

Advances in Laser Processing

Abstract This guide outlines recent advances in the various methods of laser technology and appropriate manufacturing applications. Each process has unique requirements and matching the laser source to the project is essential for developing a robust solution.

Study of highly reflective ceramic glaze coating and laser irradiation effects

The rapid development and wide application of laser technology, together with the gradually increased output energy of lasers, pose a great threat to safety. Therefore, the demand for anti-laser is urgent. Highly reflective coatings can dissipate large incident laser energy through reflection. In this paper, zirconium silicate (ZrSiO4) highly reflective ceramic glaze coatings were prepared on both ceramic and metal substrates. Their macro and micro structure evolution treated at different heating temperatures were studied. The reflectivity of the coatings was on average 85% over the range of 400 and 2400 nm and reaches a maximum of 94% at 1064 nm. The coatings on ceramic substrates showed good stability when irradiated under high-energy continuous laser with power density of 2000 W/cm2 for 60 s. On the other hand, the coatings prepared on metal substrates formed a layer of dense, glaze-like material after high-energy continuous laser irradiation with power density of 500 W/cm2 for 10 s or 1000 W/cm2 for 5 s, demonstrating good anti-laser performance.

Laser Light as an Emerging Method for Sustainable Food Processing, Packaging, and Testing.

In this review article, we systematically investigated the diverse applications of laser technology within the sphere of food processing, encompassing techniques such as laser ablation, microbial inactivation, state-of-the-art food packaging, and non-destructive testing. With a detailed exploration, we assess the utility of laser ablation for the removal of surface contaminants from foodstuffs, while also noting the potential financial and safety implications of its implementation on an industrial scale. Microbial inactivation by laser shows promise for reducing the microbial load on food surfaces, although concerns have been raised about potential damage to the physio-characteristics of some fruits. Laser-based packaging techniques, such as laser perforation and laser transmission welding, offer eco-friendly alternatives to traditional packaging methods and can extend the shelf life of perishable goods. Despite the limitations, laser technology shows great promise in the food industry and has the potential to revolutionize food processing, packaging, and testing. Future research needs to focus on optimizing laser equipment, addressing limitations, and developing mathematical models to enhance the technology's uses.

Spot laser ranging system for analysing surface features of concrete: a case in characterising concrete frost damage

ABSTRACT Surface damage of concrete induced by freezing and thawing (F-T) cycles in cold regions is characterised by peeling and pits as features of the damaged concrete surface, which needs characterising before repairing. A spot laser ranging system was established with high accuracy, and its ability to detect concrete surface features was evaluated. A 50 mm × 50 mm zone on a surface of C30 concrete specimen, with 2550 measurement points in it, was defined to obtain vertical displacements and other parameters. Mean vertical displacement of measurement points increase with F-T cycles. Effectiveness of the proposed method to characterise concrete surface damage is verified by significant regression relationship between mean vertical displacement and mass of scaling substances per unit area. Analysis of other parameters reveals that frost pit’s depth increases within initial 8 F-T cycles, while its cross-sectional area increases in the subsequent 12 F-T cycles. However, in the final 8 F-T cycles, frost pit’s cross-sectional area increases more significantly. Thus, the system is well performed in detecting frost pits on concrete surface non-destructively. The insights prolongate application of laser technology, which provides a new perspective to study the evolution of surface damage of concrete subjected to F-T cycles.

Effect of laser surface texture on the adhesion performance of CFRP/Mg laminates

ABSTRACT To investigate the enhancement mechanism and effect of laser treatment on the performance of an interface between a carbon-fiber-reinforced polymer and magnesium (CFRP/Mg), finite element simulations and experiments were conducted to demonstrate the macroscopic and microscopic failure processes of the laser-treated interface. Based on the high controllability of the groove parameters in laser machining, the quantitative relationship between the texture parameters and the shear properties of the CFRP/Mg interface was analyzed. In addition, shear tests and simulations of the laser-treated interfaces with different groove parameters were performed. Increasing the groove depth and decreasing the groove spacing effectively improved the shear strength of the CFRP/Mg interface. In addition, the reliability of the interface cohesion parameters obtained using the representative volume element model was verified by experiments and simulations, which is important for the application of laser technology to composite laminates.

Use of lasers in gastrointestinal endoscopy: a review of the literature

Lasers emit highly directional light with consistent wavelengths, and recent studies have demonstrated their successful applications in gastrointestinal endoscopic therapy. Although argon plasma coagulators (APC) became the preferred treatment option due to improved safety profile and lower costs, advancements in laser and optic fiber manufacturing have reignited interest in laser treatment. Different laser wavelengths have distinct features and applications based on their tissue absorption coefficient. Lasers with shorter wavelengths are effectively absorbed by hemoglobin, resulting in a good coagulation effect. Near-infrared lasers have ability to ablate solid tumors, while far-infrared lasers can make precise mucosal incisions without causing peripheral thermal damage. Lasers have proven to be highly applicable to endoscopy devices such as endoscopes, endoscopic ultrasound (EUS), double-balloon enteroscopes (DBE), and endoscopic retrograde cholangiopancreatography (ERCP), making them a potent tool to enhance the effectiveness of endoscopic treatments with minimal adverse events. This review aims to help readers understand the applications and effectiveness of lasers in gastrointestinal endoscopy, with the potential to promote the development and application of laser technology in the medical field.

[The development of laser technologies in vitreoretinal surgery (publications review)].

The article presents review of scientific publications on development of laser treatment methods in vitreoretinal surgery. The use of photo-therapy in medicine dates back to ancient times, when people began to use sunlight as treatment of various diseases. The heyday of photo-therapy falls on the second half of the XIX century, which was associated with the invention of first electric lamps. In 1960, T. Maiman developed the world's first laser, revolutionizing precision and control of light delivery. This was the beginning of heyday of laser surgery primarily in ophthalmology, where potential of lasers was instantly recognized. The subsequent discovery of argon laser in 1964 by W. Bridges (USA) marked new era in retinal photo-coagulation. Then new types of lasers with various systems of delivering laser radiation appeared that significantly expanded range of application of laser technologies in ophthalmology and vitreoretinal surgery. Currently, the lasers are applied in oculoplasty, refractive and corneal surgery, in laser support of phacoemulsification of cataract, in treatment of glaucoma, in laser coagulation of retina and thermotherapy. In vitreoretinal surgery laser technologies remain at the level of the XX century. Thus, they are still applied only for endolaser coagulation of retina. And this despite the fact that there is immense potential for applying lasers as "laser scalpel" to remove vitreous humor, epiretinal fibrosis, retinotomy and choroidotomy.

The Use of Lasers in Pediatric Dentistry: Applications, Benefits, and Limitations

The application of laser technology in pediatric dentistry holds immense promise for improving the quality of care and treatment experiences for young patients. Laser technology offers efficient methods for diagnosing and addressing oral and dental issues in children, encompassing both soft and hard tissues. Research indicates that the use of lasers in restorative, pulpal, and surgical procedures enhance children's cooperation and results in better care quality. Different kinds of lasers, including laser fluorescence (LF), argon lasers, erbium lasers, and CO2 lasers, are used in a range of dental applications, such as identifying, preventing, and treating cavities, as well as performing various other dental procedures. Laser technology also offers benefits in endodontics, soft tissue applications, trauma management, pain relief, and orthodontics. However, the implementation of lasers requires specialized training, initial investment costs, and careful infection control measures. Despite these limitations, lasers hold the potential to become a standard approach in pediatric dentistry, revolutionizing the way oral and dental issues are diagnosed and treated in young patients.

Experimental study on laser propagation characteristics in local air turbulence disturbed by coherent acoustic waves

The existence of atmospheric turbulence seriously restricts the application of laser technology. However, the acoustic wave will affect the air density during the propagation process, change the original structure of the air turbulence, and then affect the propagation of the laser in the air turbulence. To study the effect of disturbance of atmospheric turbulence by acoustic waves on laser propagation, the propagation characteristics of lasers in local atmospheric turbulence under coherent acoustic wave perturbation are investigated experimentally. First, a coherent acoustic wave generator and a closed local air turbulence simulation device are designed. The propagation experiments of laser in a closed local air turbulence environment disturbed by coherent acoustic waves are carried out. It is found that the coherent acoustic wave will interfere with the wave reflected from the inner wall of the closed local air turbulence simulation device, and the sound pressure forms a regular standing wave intensity distribution pattern. Moreover, the variations of laser beam drift fluctuation variance, scintillation index, and beam diameter with coherent acoustic wave frequency, power, and sound source array position are studied. The results show that the original structure of air turbulence will be changed in the process of coherent acoustic wave propagation, which will affect the beam drift fluctuation variance, scintillation index, and beam diameter changes of laser propagation in air turbulence. The beam drift fluctuation variance, scintillation index, and beam diameter change regularly with the change of the frequency and power of the sound source. Changes of the fluctuations with frequency are relatively gentle, whereas changes with power are severe. This paper explores the influence of coherent acoustic waves disturbing air turbulence on laser propagation characteristics, and the research results provide a basis for improving or disturbing laser propagation performance in atmospheric turbulent environments.