Journals
2026 EN
AhuirTorres Juan I. · Franciosa Pasquale · Öpöz Tahsin T.
+3 more
Laser surface texturing can improve the functional properties of metallic materials, with the texture shape being a crucial factor. The spatial light modulator (SLM) is used to design the shape of individual textures. However, generating deep microtextures with precise shapes on metallic materials currently requires extended processing times, limiting their use in industrial applications. This study investigates the generation of the microtexturing patterns with various shapes on stainless steel 316 L surface using a SLM. The method combining computer‐generated holograms with images demonstrates high energy fluence efficiency. The holograms determine the reconstruction distance, shape, and size of the textures. Patterns of the textures with various complex shapes (e.g., circular, triangle, square, hexagon, and other), 6–12 μm depth and 50–70 μm width are achieved using only 5 pulses (200 μs per texture) and 25 kHz pulse frequency rate. This method achieves texturing of 10 × 10 mm areas with various shapes in just 2 s, offering a processing speed ≈500 times faster than current state‐of‐the‐art ultrashort laser pulse techniques, significantly advancing the efficiency of microtexturing processes.
Journals
2026 EN
Hou Aiqiang · Yi Zao · Chen Xifang
+6 more
Zero‐dimensional (0D) perovskite derivatives A 4 PbCl 6 (A = Li, Na, K, Rb, Cs) are promising for optoelectronic applications due to their unique properties. However, synthesizing pure‐phase samples is challenging, and the impact of A‐site cation substitution remains less explored. Addressing these challenges, first‐principles calculations based on density functional theory (DFT) are employed to investigate the electronic and optical properties of A 4 PbCl 6 perovskite derivatives. The calculations reveal that the substitution of A‐site cations not only modifies the lattice parameters but also alters the distribution of the local electrostatic field within the crystal. These changes lead to variations in the electron density around the Cl and A atoms, thereby tuning the electronic structure and optical properties of the system. Specifically, Cs 4 PbCl 6 exhibits the highest extinction coefficient in the ultraviolet (UV) region, indicating enhanced optical activity, while K 4 PbCl 6 shows greater transparency due to its lower extinction coefficient. The results not only elucidate the impact of A‐site cation substitution on the properties of 0D perovskite derivatives but also provide essential theoretical insights for the rational design of new optoelectronic materials, particularly for UV detection and transparent applications.
Journals
2026 EN
Mihalko Claire A. · Lu Juanjuan · Zhang Yizhi
+8 more
Successful tuning of the metal‐to‐insulator transition (MIT) near room temperature for VO 2 thin films has been previously reported via a variety of methods, from strain and defect engineering to energy band restructuring. In this study, a nanocomposite VO 2 design is integrated on glass substrates resulting in tuning the transition, morphology, and optical and electrical properties. Specifically, VO 2 ‐Au nanocomposite and VO 2 thin films are grown using pulsed laser deposition on glass with a ZnO buffer layer. The variations in film composition and buffer layer result in unique morphology, phase change properties, and optical properties. Notably, the introduction of the ZnO buffer layer results in a redshift of the surface plasmon resonance wavelength and unique epsilon‐near‐zero characteristic for the buffered films. Overall, this work discusses the effect on the tuning of the MIT and optical properties through a novel multifaceted approach using both defect engineering and energy band restructuring. These VO 2 and VO 2 nanocomposite films integrated on amorphous glass substrates show promise for future applications in sensing, thermochromics, and optical switching.
Journals
2026 EN
Novák Ondřej · Herranz Gervasi · Veis Martin
Topological photonics offers a robust platform for controlling light, with applications such as backscattering‐immune edge‐transport and slow‐light propagation. A comprehensive and automated framework is presented for the design and characterization of symmetry‐protected interface modes in 2D photonic crystals. The main tool in this approach is an iterative band‐connection algorithm that ensures symmetry consistency across the Brillouin zone, enabling reliable reconstruction of bands even near degeneracies. Complementing this, a data‐driven symmetry classification method is introduced that constructs comparator functions directly from eigenmode data, removing the need for predefined symmetry operations or irreducible representations. These tools are particularly suited for generative or parametrized geometries where symmetries may vary. Using this framework, example structures exhibiting obstructed atomic limits, characterized by Wannier center displacements and mode inversions, are identified. The tradeoffs between interface mode dispersion and bulk bandgap size are analyzed, and how the number of photonic crystal periods at the interface governs the emergence and robustness of topological modes is shown. Finally, the scalability of this approach across material platforms and operating wavelengths, including the telecommunication range, is demonstrated. These contributions enable physically grounded and fully automated design of topological photonic interfaces, paving the way for large‐scale exploration and optimization of complex photonic structures.
Journals
2026 EN
Zhu Yingguang · Hu Yonglan · Cui Yingjie
+7 more
After decades of development, organic light‐emitting diode (OLED) technology has matured significantly. OLED displays are now ubiquitous in consumer electronics and household appliances. As another major application branch, OLED lighting has also entered the automotive market. Futhermore, owing to its inherent characteristics such as a surface light source, thinness, and flexibility, OLEDs demonstrate unique advantages for phototherapy and attract growing research interest. Clinical studies validate the efficacy of OLEDs in both photobiomodulation and photodynamic therapy. However, to unlock their full potential, key challenges regarding the emission wavelength range, optical power density, and mechanical flexibility must be addressed, as they currently limit therapeutic scope. Future advancements may enable precise spatial control for targeted therapy, while integration with photodetectors could facilitate combined diagnosis and treatment. This review comprehensively outlines OLED applications in phototherapy, identifies current challenges, and discusses future prospects, providing valuable insights for the field's development.
Journals
2026 EN
Nie Haitao · Zhao Yaping · Zhang Yifei
+4 more
Hyperspectral imaging in the visible spectrum offers significant potential for diverse applications, but is often constrained by bulky hardware and limited robustness in low‐light conditions. To overcome these challenges, a simulation‐based proof‐of‐concept for a metasurface‐encoded single‐pixel hyperspectral imaging system (MESH) is presented, in which structured spatial modulation is combined with a compact set of 50 broadband metasurface filters designed using a binary pattern generation strategy to ensure low interfilter correlation. Hyperspectral datacubes comprising 301 channels from 400 to 700 nm are reconstructed via a sparsity‐constrained optimization algorithm, while a physics‐enhanced deep learning model is further introduced to enable fast and accurate recovery. Simulation results demonstrate that MESH achieves a spectral resolution of 1.17 nm. Even at a total compression ratio of 2.1%, the deep learning model maintains high reconstruction quality, with a peak signal‐to‐noise ratio of 30.96 dB, structural similarity of 0.8526, and spectral angle mapping of 0.0742 rad, indicating accurate intensity recovery, structural preservation, and spectral integrity. The present study provides a simulation‐based verification of feasibility and design guidelines, laying the groundwork for future experimental validation of the MESH system, which is expected to further demonstrate its practical applicability and performance for deployment in low‐light and resource‐constrained environments.
Journals
2026 EN
Liu Dingbang · Chen Yusa · Cao Yunhao
+6 more
Achieving high‐performance, polarization‐insensitive broadband absorption with wide angular tolerance remains challenging for perfect absorbers. This work proposes a novel Ge 2 Sb 2 Te 5 (GST) metasurface absorber based on a metal–insulator–metal structure, featuring dual‐sized cylindrical amorphous GST meta‐atoms, a MgF 2 spacer, and a gold reflector. The design exhibits fourfold rotational symmetry, enabling polarization‐independent operation. By spectrally overlapping the magnetic and electric dipole resonances supported by the dual meta‐atoms, an average absorptivity of 94% from ultraviolet to near‐infrared is achieved. Moreover, the absorber maintains 83% average absorption even at 70° incidence, showing remarkable angular tolerance. Optical switching is also feasible via GST phase modulation. These attributes make the proposed absorber highly promising for integrated optoelectronic applications.
Journals
2026 EN
Gegevičius Rokas · Ledzinskas Ignas · Chmeliov Jevgenij
+4 more
In some applications, perovskite light‐emitting diodes (PeLEDs) shall operate in pulsed mode. The generation of high‐intensity light pulses requires PeLED driving by high‐power electrical pulses, which can lead to deterioration of PeLED performance and their degradation. Contrarily, PeLEDs operating in a nonconventional regime, based on the so‐called overshoot effect, enable the generation of short, high‐intensity optical pulses at relatively low driving pulse power. Here, the generation of overshoot pulses (OSPs) by FAPI PeLEDs is analyzed. The intensity and shape of the OSPs are determined not only by the driving (injection) pulse parameters but also by the offset voltage applied between the injection pulses and the afterpulse applied after the injection pulse. The offset voltage determines the distribution of the mobile ions, which strongly affect the internal electric field during the pulse action and after its termination, thus strongly affecting the evolution of the conventional electroluminescence (EL) and generation of the OSPs. Meanwhile, the afterpulse voltage controls the intensity and duration of the OSPs. The intensity of the OSPs increases strongly at temperatures below ≈200 K. Mathematical modeling reproduces the EL dynamics and reveals two distinct PeLED operation modes: one that facilitates OSP generation and another that prevents it.
Journals
2026 EN
Ebrahimpanah Saba · Mozaffari Mohammad Hazhir · Farmani Ali
This research presents a pioneering plasmonic nanotweezer (PNT) designed in a bowtie configuration utilizing graphene, aimed at markedly improving optical trapping effectiveness at the nanoscale. Through the application of the particle swarm optimization (PSO) algorithm, the optimal geometrical parameters—width of 189.24 nm, length of 234.19 nm, and a gap distance of 6.2 nm—that optimize electromagnetic field localization are determined. The transfer matrix method is employed to simulate electromagnetic wave transmission, while 3D finite‐difference time‐domain simulations confirm the emergence of intense plasmonic hotspots at the vertices of the bowtie, which generates a trapping force of ≈6 nN W −1 for a bioparticle of 10 nm. The thermal analysis demonstrates a direct relationship between input power density and temperature elevation, achieving an impressive stability threshold of S = 1.32 at a mere 1 mW μm −2 —substantially lower than the 6 mW μm −2 typically necessary for conventional gold or silver nanotweezers. Additionally, at an input power of 10 mW μm −2 , the stability metric escalates to 13, emphasizing the resilience of the trapping mechanism. This PSO‐optimized graphene PNT not only amplifies plasmonic efficacy but also reduces energy consumption, representing a significant advancement in nanoscale optical trapping technologies for bioanalytical purposes.
Journals
2026 EN
Rahman Tanzina · Ebon Md. Islahur Rahman · Sana Amrita Kumar
+1 more
This work presents the design and numerical simulation of a long‐wave infrared microring resonator sensor employing Ge 2 Sb 2 Te 5 (GST) as the core material, integrated on a ZnSe substrate with air cladding utilizing the finite‐element method in COMSOL Multiphysics. The study evaluates main properties such as effective mode index, power confinement factor, propagation loss, as well as transmission spectra across various modes. The proposed structure demonstrates strong confinement and minimal loss at 8 μm, achieving high Q ‐factors of 7.9 × 10 3 and 7.3 × 10 3 . The limit of detection is found to be 11.59 × 10 3 refractive index unit (RIU) and 52.32 × 10 3 RIU for the output and drop port, respectively. The GST ring resonator is exploited for label‐free gas and biosensing applications, successfully detecting refractive index variations among multiple ambient gases, cancerous and normal cells, as well as viruses and bacteria. The sensor exhibits high sensitivity, a narrow full‐width at half‐maximum, and wavelength tunability in response to subtle refractive index shifts. These findings establish the GST‐ZnSe platform as a promising candidate for compact, high‐performance integrated photonic sensors for biomedical diagnostics and environmental monitoring.