Optical and Quantum Electronics最新文献

We study theoretically the analytical expression of a pulsed chirped modified anomalous vortex beam (MAVB) across biological tissue using the integral of Huygens-Fresnel and the Fourier Transform method. Spectral modifications for pulsed chirped MAVB are examined across various biological tissues, including human upper dermis, mouse intestinal epithelium, and mouse deep dermis. Graphical representations are employed to analyze the beam parameters, biological tissue effect properties, and transverse positions on the analyzed beam. Results reveal that the structure constant of refractive index, chirp parameter, pulse duration, and variations in beam parameters can impact the intensity of the spectral beam. The on-axis spectral intensity shows a blue shift, whereas the off-axis spectral intensity demonstrates a red shift as the radial coordinates increase. It is expected that the results of this study will greatly enhance progress in disease and treatment, particularly in cancer research. By analyzing variations in intensity distribution, scientists can improve their ability to identify and diagnose diseases more effectively.

Organic semiconductor blends offer a promising platform for low-cost and environmental friendly optoelectronic devices, yet their performance is often limited by incomplete spectral absorption and suboptimal charge-transfer characteristics. In this work, we investigate the optical and structural properties of two binary blends (VOPcPhO: PC₇₁BM and PCDTBT: PC₇₁BM) and a ternary blend (VOPcPhO: PCDTBT: PC₇₁BM) to identify the advantages of combining complementary donor materials in a bulk-heterojunction system. The ternary film exhibits markedly enhanced photoactive behavior, achieving a high absorption coefficient of ~ 1.8×10⁵ cm^− 1 at 3.56 eV, a refractive index of ~ 2.4, and an extinction coefficient of ~ 3.54 × 10⁴ cm^− 1. Its optical conductivity increases to ~ 6.43 × 10¹⁵ S·cm^− 1, surpassing both binary counterparts. Improved film morphology and favorable energy-level alignment further promote stronger light-matter interaction and more efficient charge-transfer pathways. These combined enhancements demonstrate that the VOPcPhO: PCDTBT: PC₇₁BM ternary blend outperforms the binary systems in both optical response and structural quality, highlighting its strong potential as an effective active layer for next-generation high-performance optoelectronic devices.

The ability of structured light to reconstruct after partial obstruction, known as the self-healing phenomenon, has attracted considerable attention for applications in imaging, optical communication, and quantum technologies. While Bessel and Airy beams have been extensively studied, the self-healing behavior of Hermite–Gauss (HG) beams remains less well quantified. In this work, we systematically investigate the self-healing properties of six HG modes (HG₀₁, HG₁₀, HG₁₁, HG₁₂, HG₂₁, HG₂₂) under three classes of obstructions: circular disks, vertical strips, and rectangular fringes. Both intensity- and amplitude-based similarity measures are employed within the normalized self-healing degree (SHD) framework, providing a rigorous and comparable metric of recovery efficiency. Numerical simulations reveal that higher-order modes, particularly HG₂₂, demonstrate superior resilience, achieving SHD values above 1.1 even for moderate obstructions, whereas lower-order modes exhibit incomplete recovery. Geometry–mode alignment effects are also observed, with HG₁₁ showing enhanced robustness under strip obstructions. Importantly, amplitude-based SHD is consistently lower than intensity-based SHD, confirming that apparent intensity recovery can overestimate robustness when phase fidelity is critical. These findings establish a comprehensive quantitative picture of HG self-healing and offer practical insights for designing resilient, structured beams in realistic optical environments.

This study proposes a wideband graphene-based metasurface absorber on a quartz substrate, offering enhanced absorption, intrinsic tunability, and suitability for advanced sensing and biomedical diagnostics. Unlike conventional absorbers requiring external components, its resonance frequency is dynamically tuned by varying graphene’s relaxation time (0.1–0.3 ps), enabling efficient frequency modulation with simplified structure. The metasurface demonstrates high sensitivity to refractive index variations of hemoglobin and urine, directly linked to clinically relevant parameters such as glucose and uric acid. It achieves maximum sensitivity of 2.0 THz/RIU (FOM = 11.1/RIU) for hemoglobin and 6THz/RIU (FOM = 24/RIU) for urine. Additionally, it enhances SNR and suppresses EMI, improving MRI imaging. These features establish it as a promising platform for next-generation terahertz sensing and EMI-shielding applications.

Undoped and Co-doped ZnO films were deposited on glass substrates by dip-coating. The sol-gel technique was employed to prepare a series of precursor solutions by dissolving zinc acetate dihydrate (ZnAc) and stochiometric amounts of cobalt acetate dihydrate (CoAc) in 2-methoxyethanol to achieve target Co concentrations of 1, 3, 5, and 7 wt%, with the addition of mono-ethanolamine (MEA) as a stabilizer. All films were subsequently annealed for 2 h 30 min at 500 °C. To investigate the effect of Co doping, and understand the morphological, structural, and optical characteristics of the films, several techniques were employed. The X-ray diffraction (XRD) patterns of all films showed hexagonal crystals of the ZnO wurtzite phase with nanometric crystallite sizes (less than 20 nm). The AFM images revealed irregularly shaped grains with a non-uniform surface distribution. All samples exhibited high transmittance in the visible region and a strong absorption edge in the UV region. Photoluminescence (PL) spectroscopy revealed a non-monotonic evolution of the UV emission and a general quenching of the visible band with Co concentration. Photocatalysis showed a progressive improvement as the Co doping increases. In contrast, the antibacterial activity revealed a divergence at 7% doping, where efficacy against E. coli decreased while the inhibition of S. aureus continued to increase.

Glasses were prepared using a melt-quenching technique with the following composition: 55 mol% Li₂B₄O₇ and (45-x) mol% Pb₃O₄- (x) mol% CuO, where x takes values of 5, 10, 15, 20 and 25 mol%. Differential thermal analysis (DTA) confirmed the formation of glass, revealing that the glass transition temperature increased from 300 °C to 317 °C as the copper content rose to 20 mol%. However, beyond this point, the glass transition temperature began to decrease. Some samples displayed two glassy phases, as indicated by the presence of two distinct glass transition temperatures. All glass samples demonstrated high thermal stability and effective glass-forming ability, with properties improving as the copper content increased. X-ray diffraction (XRD) spectra confirmed that the samples were amorphous in nature. The structural, optical, and luminescence properties were investigated using Fourier-transform attenuated total reflectance (ATR) FTIR, X-ray photoelectron spectroscopy (XPS), UV/Vis/NIR spectroscopy, and a spectrofluorometer. FTIR spectra indicated that the glass samples contained vibrations from BO₄, BO₃, and PbO₄ groups. As the amount of copper oxide increased, the concentration of non-bridging oxygens (NBOs) also rose. The ratio of BO₄ to BO₃ increased up to 20 mol% of CuO and subsequently began to decrease. According to the XPS results, the ratio of NBOs to bridging oxygens (BOs) increased with CuO content up to 15 mol%, after which it declined. This initial rise suggests an increase in polarization and a loosening of the glass network structure. Additionally, copper ions were present in both Cu²⁺ and Cu⁺ valence states, in line with the optical absorption results. The ratio of Cu²⁺ to Cu⁺ increases to 6 as the concentration of copper rises. As the copper oxide content increased, the optical band gap decreased from 2.9 eV to 1.7 eV. Luminescence from copper ions produced emissions in various colors, including green, greenish-yellow, orange, and pink, depending on the excitation wavelengths, which ranged from 270 nm to 350 nm without a filter. Using a filter, the emissions took on a blue hue at the same excitation energy.

The energy crisis has attracted widespread attention in scientific research, with renewable energy production—particularly through solar cells—considered a promising solution. Over the past decades, numerous studies have focused on the active materials used in solar cells. Investigating the optical properties of these materials is crucial for applications in solar cells, optical filters, and other optoelectronic devices. Traditional methods such as the Schuster–Kubelka–Munk (SKM) remission function and Tauc’s plot are commonly used to estimate the optical band gap; however, they provide only the energy gap value. More comprehensive information—such as the energies of the conduction band, valence band, and Fermi level—is vital for selecting compatible transparent conductive layers. This study presents a novel quantum–classical approach to the well-known quantum mechanics problem of the rectangular potential barrier. Using a Modified Schrödinger Equation, the proposed model directly estimates the energies of the conduction band, valence band, Fermi level in intrinsic semiconductors, and intermediate state (donor or acceptor) involved in indirect transitions, as well as the optical diffusion length and majority carrier type. The model is validated using experimental data and shows a strong correlation between predicted and observed values. It represents a valuable tool for the optical characterization of materials used in solar cells, optoelectronic devices, and optical filters.

In this study, the detection capability of biological threat agents was investigated using a multispectral nanoplasmonic aptasensor based on a Di-supercell metamaterial. This configuration consists of two supercells: one circular and the other square, with a square cell placed inside a circular cell, creating the proposed structure. The three-dimensional finite difference time domain (FDTD) simulation method also confirmed the validity of the findings. The detection of biomolecules in traditional biosensors, especially in the presence of low analyte concentrations, is challenging and requires the use of sensors with superior sensitivity (S). Based on the results obtained, the designed structure exhibits sensitivities of 539.43 and 644.29 nm/RIU in modes I and II. The presence of two resonance modes in this structure makes it an ideal choice for multispectral applications. Our findings suggest that this has structure substantial promise for a variety of biological applications. In this study, both silver and gold metals were evaluated as plasmonic materials. Our novel design features a unique arrangement that allows for maximum interaction of cells with the target analyte. This optimized structure provides a suitable platform for enhancing the sensitivity and accuracy of analyte detection and, given the level of sensitivity, is an appropriate option for the identification of biological threat agents.