Plasmonics最新文献

Herein, MoS₂-50 nm was integrated with SiO₂-50 nm utilizing a solid-state reaction process (SSRP). Various weight proportions of SiO₂@MoS₂ composite-reinforced nanoparticles (CRNPs) were presented into a ternary polymeric matrix (TPM) comprising PEO, sodium alginate, and PVA by the casting process. SEM findings revealed that PEO/sodium alginate/PVA had a well-ordered and homogenous surface topography with microcracks and cavities. Nonetheless, the improved dispersion of CRNPs without accumulating into TPM resulted in a stable dropping in holes and cracks. XRD patterns corroborated the crystallographic descriptions, revealing the semi-crystalline structure for all composite films. The average crystallite size declined from 21.685 nm (S₀) to 17.961 nm (S₂) and subsequently developed with CRNPs incorporation to 21.926 nm (S₃) and 23.289 nm (S₄), with a nominal average lattice strain of 3.689 × 10⁻³ after integration. The optical results showed an enormous upturn in optical absorbance values coupled by appearances of surface plasmonic resonance at about (651 nm) upon CRNPs integration technique. Enclosure of CRNPs resulted in considerable decline in direct and indirect bandgap values from 5.2 to 1.8 eV and 2.5 to 1.1 eV, respectively, and such results are almost identical to dielectric constants. Extraordinarily, dielectric values improved with the development of CRNP addition and frequency values. Fabricated membranes demonstrate significant antibacterial effect, with greatest zone improvement (D = 20–26 mm) for Escherichia coli and (D = 22–37 mm) for Staphylococcus, resulting in the bacteria being thawed inside the inhibition zones. The resultants are considered key for sunscreens, energy storage, food preservation, and unique plasmonic applications.

Perovskites possess exceptional optical and electrical properties, making them promising candidates for significantly enhancing solar cell efficiency. In this simulation study, we utilized the Solar Cell Capacitance Simulator to numerically investigate the performance of solar cells based on the FTO/ETL/AL/Spiro-OMeTAD/Au configuration. The analysis focused on various perovskite active layers—FAPbI_₃, CsGeI_₃, and CsGeI_₂Br—and electron transport layers—SnO_₂, TiO_₂, and WO_₃. Key parameters studied included layer thickness, doping density, and defect density. The simulation results revealed that the optimal power conversion efficiency of 21.22% was achieved using WO₃ as the electron transport layer, with a thickness of 0.23 μm, a defect density of 1 × 10¹⁵ cm⁻³, and a doping density of 5 × 10²⁰ cm⁻³. Additionally, for the perovskite active layer, a CsGeI_₃ composition with a thickness of 0.65 μm, a defect density of 5 × 10¹⁴ cm⁻³, doping density of 1 × 10¹⁶, and a bandgap energy of 1.363 eV demonstrated superior performance, delivering a power conversion effecincy of 28.1%. This exceeded the performance of FAPbI₃ (bandgap energy, 1.51 eV) and CsGeI_₂Br (bandgap energy, 1.579 eV). These findings suggest that the FTO/WO_₃/CsGeI_₂Br/Spiro-OMeTAD/Au structure, particularly with optimized WO₃ and CsGeI₃ layers, holds great potential for high-efficiency solar cell fabrication. Furthermore, machine learning models with random forest algorithim predicted the performance metrics of the investigated solar cells with an accuracy of 88.6%, and power conversion effeciency prediction with R² of 0.6234 underscoring the potential of machine learning in optimizing solar cell design and performance.

Recent scientific and technological breakthroughs have led to the development of highly sensitive biosensing technologies for pathogen identification. Surface plasmon resonance (SPR) has emerged as an environmentally friendly and efficient label-free detection technique in clinical research, particularly for examining biomolecular interactions, including those involving haemoglobin. Hematologic malignancies include several forms of malignancy that mostly impact the blood, bone marrow, and lymphatic system. This research introduces an innovative surface plasmon resonance (SPR) biosensor utilizing silver (Ag), perovskite oxide (PO), and MXene (Ti₃C₂Tₓ) nanostructures for the precise detection of blood cancer via haemoglobin concentration assessment. SPR sensors provide label-free, real-time detection, rendering them suitable for clinical diagnostics, especially in the identification of hematologic malignancies like leukaemia, which is marked by changed haemoglobin levels. To improve sensor performance, we methodically examined different perovskite oxide materials (BaTiO₃, SrTiO₃, CaTiO₃, and PbTiO₃) and tuned their thicknesses. Among these materials, PbTiO₃ exhibited exceptional sensitivity (up to 664.28°/RIU at a thickness of 5 nm), although CaTiO₃ displayed the highest quality factor (QF = 110 RIU⁻¹), signifying remarkable resonance sharpness and detection precision. The integration of MXene layers enhanced sensitivity owing to their remarkable optical and electrical characteristics, with a peak sensitivity of around 580°/RIU. Nonetheless, the incorporation of MXene significantly expanded the resonance dip, resulting in a minor decrease in the quality factor. A comprehensive investigation revealed an optimum arrangement (Ag-PbTiO₃-MXene) with layer thicknesses of d₂ = 4 nm (PbTiO₃) and d₃ = 1 nm (MXene), achieving an exemplary equilibrium between elevated sensitivity (557.14°/RIU) and substantial QF (96.05 RIU⁻¹). These findings underscore the essential trade-offs between sensitivity augmentation and resonance sharpness, highlighting the necessity of meticulous material selection and thickness optimization. The suggested SPR biosensor design exhibits considerable promise for sophisticated biomedical diagnostics, especially for the early and precise identification of haematological malignancies by accurate haemoglobin concentration assessment.

Enhancing the ability of solar cells to capture solar photons and improve light absorption plays a crucial role in increasing the power conversion efficiency (PCE) of solar cells. This study proposes an innovative thin-film solar cell structure that integrates photonic crystals, gratings, and plasmonic gold nanoparticles (Au NPs) to form a highly efficient optical architecture. By designing a light-trapping structure (LTS) consisting of periodically arranged grating ITO and photonic crystal TiO₂ on the top layer of the CdTe thin-film solar cell, and embedding Au NPs within the CdTe absorption layer, the optical path length of light within the cell is effectively extended, enhancing the interaction between light and the absorbing material. This paper conducts coupled optical and electrical simulations, and the results show that the proposed structure achieves nearly perfect light absorption in the visible spectrum, demonstrating excellent short-circuit current density (J_sc) and PCE performance. Compared to the unoptimized cell, the J_sc increases by 5.422 mA/cm² and the PCE improves by 7.932%. This achievement not only surpasses the performance level of conventional thin-film solar cells but also opens new possibilities for more efficient and environmentally friendly solar energy utilization.

This study presents a numerical analysis of a surface plasmon resonance (SPR) biosensor with enhanced sensitivity, figure of merit (FoM), and penetration depth (PD) at infrared wavelengths. The sensor design incorporates a carbon nanotube (CNT) layer combined with a graphene layer, optimized for biomolecule detection at an excitation wavelength of 1550 nm. The graphene layer functions as a biorecognition element (BRE), enabling biomolecule attachment due to its strong adhesive properties. The proposed sensor achieves a maximum sensitivity of 354.08°/RIU and a PD of 1298.11 nm with minor refractive index (RI) changes in the sensing medium (1.37–1.38). The structure is effective for RI values ranging from 1.32 to 1.42. With notable improvements in FoM and limit of detection (LoD), the biosensor demonstrates a high potential for precise biomolecule detection. Further, as an application, the proposed biosensor’s performance is evaluated for detecting cancers such as skin, cervical, blood, and breast cancer. Although this study is based exclusively on simulations, experimental studies can be carried out in the future to validate the numerical results obtained.

Conventional metasurfaces are usually constrained by static material compositions and geometric configurations, exhibiting limited capabilities for dynamic electromagnetic applications. On the other hand, although the dynamic and reconfigurable metasurfaces have been extensively studied, their single-dimensional modulation mechanisms often fail to address the requirements of complicated electromagnetic environments. To address these limitations, a significant multifunctional terahertz metasurface from the integration of vanadium dioxide, graphene, and photosensitive silicon is proposed in this work. This unique design combines the strong field-localization characters of bound states in the continuum (BIC) and the advantages of the terahertz spectrum to achieve simultaneous modulations in terahertz electromagnetic wave absorption and sensing function. Remarkably, the BIC mode with an infinite quality factor can transform into a quasi-BIC (QBIC) mode with a finite quality factor by adjusting the system’s asymmetry; at the same time, the synergistic modulations of conductivity, optical response, and phase transition can overcome the limitations of single-dimensional tuning. Furthermore, adjusting the conductivity of VO₂ in the device enables a switch between a BIC mode and a narrowband absorption character. Based on the narrowband absorption character, a theoretical framework for high-sensitivity dielectric sensing with an excellent 671 GHz/RIU sensitivity is further established. The proposed multi-mechanism synergistic tuning strategy offers novel insights into the development of dynamically adaptable terahertz devices and ultrasensitive sensors.

This paper develops the 4-port graphene-silicon antenna in the THz frequency range. Two-diagonally placed S-formed patches excited silicon ceramic, and two stair aperture excited silicon pieces make up the designed multi-port radiator. To lessen the disruption from the field elements, these two distinct kinds of antenna components are designed to illuminate in complementary directions. This feature could potentially provide a stable wireless connection. With the assistance of change in the chemical potential of graphene coating, the proposed aerial becomes frequency tunable. Circular waves are produced from all ports in such a way (polarization diversity) to advance the separation level and diversity functioning. Designed THz aerial works in between 3.2 and 3.82 THz having inter-port separation above 30 dB. The observed coinciding axial ratio (AR) range of the suggested multi-port aerial is 0.4 THz (3.38–3.78 THz). This design may be used for THz built 6G communication systems because of all these qualities.

One of the most prominent methods for identifying an interaction between chemicals is surface plasmon resonance (SPR) which is appreciated for its capability of measuring in real-time, without labels, and with great sensitivity. This strategy is useful in a variety of fields, including medical, environmental research, and food science. Because of the large size, cost, and complicated laboratory setup SPR systems require, their use has always been confined to very controlled settings. Researchers currently work toward overcoming these challenges by designing portable devices to make SPR technologies easier to access. These smaller systems provide numerous benefits, including less expensive, easier to operate, and more convenient where tests can be done at the site or point of care. With the progress of miniaturized optics, cheap materials, integration of microfluidics, and wireless technologies, portable SPR is becoming a realistic option for immediate analysis on site. Some of the devices are even smartphone compatible or battery operated, enabling use in remote or resource limited settings. Advances in nanomaterials, 3D printing, and artificial intelligence (AI) data processing techniques have accelerated their performance and usability. In this review, we discuss advancements in portable SPR technology, paving the way for real-world applications beyond lab settings, through exploration of recent design trends, materials, and functionality, we highlight how portable SPR devices are paving the path for innovative uses in rapid, accurate, and convenient sensing in campaigns and diagnostics in various fields.

This study presents a tunable graphene-metasurface biosensor for cancer cell detection. The design features four gold-coated square resonators within silver-coated rectangular elements on a graphene substrate, optimizing electromagnetic field confinement and plasmonic response.Parametric optimization of graphene chemical potential, incident angle, and resonator dimensions yields maximum sensitivity of 2000 GHz/RIU and figure of merit of 24.096 RIU⁻¹. Linear correlation analysis demonstrates strong relationship between resonance frequency and cancer cell concentration (R² = 0.95276). Field distribution modeling confirms optimal localization at 0.88 THz.XGBoost regression modeling achieves 91% predictive accuracy for absorption measurements. The sensor demonstrates superior performance compared to existing technologies, providing enhanced sensitivity and reliability for early cancer detection applications.

This numerical work uses a surface plasmon resonance (SPR)-based Kretschmann sensor structure to examine early cancer detection. The proposed optical sensor is intended to identify different types of cancer-infected cells in the human body with refractive indices (RIs) between 1.38 and 1.401. It performs well across various RI changes, including biological solutions. The sensor is designed and analyzed using a MATLAB simulation platform based on the transfer matrix method (TMM). Characteristic parameters like sensitivity (S), full width at half maximum (FWHM), detection accuracy (DA), and figure of merit (FoM) are used to assess the suggested SPR sensor’s performance. With a maximum FoM of 166.07 RIU⁻¹ and DA of 0.465°⁻¹, the numerical findings demonstrate that the developed sensor can detect skin, cervical, blood, adrenal gland, and type I and type II breast cancer with a sensitivity of 200, 245.83, 257.14, 303.57, 353.57, and 357.14°/RIU, respectively. Based on the obtained results, we think that the proposed SPR sensor may find use in medical science for early cancer detection, which would open up new possibilities in the biosensing sector.