Diagnosing malaria necessitates quick and precise recognition of the infection's stage, since the refractive index (RI) of red blood cells varies during the parasite's life cycle. This research introduces a terahertz (Thz) photonic crystal fiber (PCF) sensor intended to identify these refractive index changes that depend on the stage. The sensor, designed with the finite element method in COMSOL Multiphysics, functions in the 1.0-2.5 THz range and exhibits high modal confinement while minimizing confinement and material losses. At 2.5 THz, the structure attains a high relative sensitivity of 99.937% for the Normal stage in y-polarization, surpassing earlier reported THz PCF sensors. The design additionally demonstrates outstanding power confinement and an appropriate effective mode area. Moreover, the sensor works well with practical manufacturing methods like 3D printing and extrusion. Machine learning analysis further validated the sensor's capability by accurately classifying malaria stages based on the derived PCF optical features. These results suggest that the proposed PCF provides an exceptionally sensitive and practical platform for label-free identification of malaria stages.

Photonic crystal (PHC) sensors offer high sensitivity for chemical detection in industrial and biomedical settings. We theoretically design and optimize a 1D binary PHC, (Si/SiO2)N/defect/(Si/SiO2)N, for broadband detection of organic analytes introduced into the central defect. Using the transfer-matrix method, we compute transmission while varying refractive-index contrast, defect thickness, period number, and incident angle. Sensitivity increases with larger defect thickness, higher incident angle, and greater index contrast. Across analysis indices 1.33–1.66, the sensor attains 1500–1990 nm/RIU. Empirical fitting equations relate sensitivity to structural/optical parameters, enabling accurate prediction and rapid optimization without repeated simulations. These results support integration of this tunable, high-performance design into real-time broadband chemical sensing systems.

Conventional optical Tamm state (OTS)-based sensors are generally limited by low sensitivity, reduced absorption efficiency, or the capacity to detect only a single parameter, hence limiting their multifunctional sensing capabilities. This study proposes a silver-enhanced one-dimensional photonic crystal (1D-PC) structure that supports multi-frequency OTS resonances for simultaneous refractive index (RI) and incident angle sensing on a single platform. The optical properties are investigated using the transfer matrix method under Bragg scattering conditions. The formation of a silver interface layer improves electromagnetic field confinement at the metal–photonic crystal interface, allowing near-perfect absorption above 0.97 at three separate absorption peaks (APs). The APs demonstrate adjustable red and blue shifts through variations in defect layer thickness and incidence angle, while the inter-peak spacing may be adjusted by modifying the number of phase layers. The RI sensor functions within the range of 1.5–2.2, exhibiting a sensitivity of 36.92 THz/RIU and an average figure of merit (FOM) of 108.62, exceeding earlier OTS-based sensors. It achieves a sensitivity of 0.556 THz/degree for angle sensing within a detection range of 30–70°, exceeding previous dual-parameter structures. The results show an enhanced dual-parameter sensing platform defined by increased absorption efficiency and higher performance metrics, suited to advanced optical measurement applications.

The lifetime and smooth action of petroleum machines is significantly affected by fuel purity. Today, a lot of deceitful dealers mix petroleum products with inferior-priced oils/components to enlarge their earnings. To address these issues, a surface plasmon resonance sensor is projected to discover the presence of kerosene concentration in petrol (gasoline). Newly, angular analyses have been commonly depleted to determine the sensitivity. The present study is proposed for the screening of kerosene concentrations in the fuel using prism coupling-based surface plasmon resonance biosensors. All the analytical works are performed by Mathematica 5.2 software, and the Origin software is expended to plot the graphs. The sensor created on the Kretschmann pattern is made up of the hybrid assembly based on beryllium oxide (BeO) and graphene layers deposited on silver film. The wavelength of the used input wave is 632.8 nm. The top sensitivity of 465.21 degree/RIU has been acquired when the kerosene concentration is 40

Water is one of the essential requirements for human life. Various types of impurities that are present in the drinking water can produce grave health concerns, affect body tissues, and may lead to death. Protozoan parasites are one of the major biological pollutants in the water, which are ordinarily transferred across during the oral-fecal path. Cryptosporidium parvum oocysts (CPO) and Giardia lamblia (GL) are two frequently observed waterborne protozoan organisms. They have different values of index of refraction (IOR). Novel detector can be established with real-time detection based on this biophysical consideration. Here, an optical surface plasmon resonance biosensor (OSPRB) is developed for discovery of CPO and GL in drinking water. Angular examination and Kretschmann design are employed to explain the conception of the setup. An angular sensitivity (AS) of 188 Deg./RIU is attained by the suggested OSPRB with very low limit of detection (LOD) of 2.64 × 10−5 RIU. Other functioning factors are calculated for offered OSPRB. The achieved outcomes indicate that the suggested OSPRB has conspicuously improved performance as contrasted to aforementioned outcomes in the literatures. The suggested OSPRB can accelerate a substantial biological detecting tool with accurate and fast sensing at early point.

High uric acid levels in humans are associated with critical health conditions such as kidney failure, gout, heart diseases, arthritis, and various physiological disorders. In order to detect uric acid, this study presents a surface plasmon resonance (SPR) biosensor that combines blue phosphorene (BlueP), Ag, indium tin oxide (ITO), graphene, and transition metal dichalcogenides (TMDCs) in an inventive hybrid architecture. The BlueP/TMDCs composite is the interactive layer with the target substance, boosting the sensor’s performance. We thoroughly evaluated detection precision, figure of merit (FOM), sensitivity, full-width half maximum (FWHM), and other important performance measures, with an emphasis on detection and figure of merit (FOM) optimization. The goal was to achieve an exceptionally high FOM for the biosensor. Preliminary findings revealed a notable FOM of 105.50 RIU-1, which significantly increased to 2638.29 RIU-1 after refining the layer thicknesses, indicating an outstandingly high value. This exceptional FOM underscores the potential of the developed SPR-based biosensor for extensive application in biosensing technology.

The level of sucrose in an aqueous liquid has an extensive scope of purposes in medications, for example, food and protein safeguarding. Here, a novel PCFB has been presented to detect various sucrose levels in an aqueous solution that has an index of refraction in the scope of 1.345–1.442. The aimed PCFB includes an easy array of rectangular cavities. The capability of this detector in sensing is appraised via applying the finite element technique (FET). The effective material loss and confinement loss have been displayed extremely lower rates for the projected PCFB. Furthermore,the projected PCFB achieves an uppermost relative sensitivity of 99.514

This research presents a one-dimensional photonic crystal structure designed for precise angle and refractive index detection through the optical Tamm state. Utilizing the transfer matrix method, the study explores system characteristics under specific Bragg scattering conditions. The proposed sensor structure incorporates a multi-frequency absorption configuration, achieving absorption rates exceeding 0.9 at three distinct frequency points. Adjustments in the incident Light angle and defect layer thickness induce red and blue shifts in the absorption peaks, while the spacing between these peaks can be controlled by the phase number and defect layer thickness. Among these configurations, one demonstrates exceptional properties, enabling the development of highly efficient refractive index and angle sensors. The structure operates as a refractive index sensor within a range of 1.3 to 2.7, with a sensitivity of 32.389 THz/RIU and an average figure of merit of 70.328. When applied as an angle sensor, it exhibits a sensitivity of 0.533 THz/degree, with a corresponding figure of merit of 1.57, covering an angular range from 30° to 70°. This innovative structure holds significant potential for enhancing sensor applications, contributing to advancements in optical detection and precision measurement.

A novel heterostructure of surface plasmon resonance (SPR) sensors for various analytes has been proposed. The suggested sensor is highly sensitive to the changes in index of refraction detecting media. It is made of Ag, PtSe2, and graphene. A study on the performance of graphene thickness, PtSe2 thickness, and Ag thickness has been performed. It is a simulation-based study using the transfer matrix method (TMM) method, while Maple 18 Software has been used to simulate the structure. Maximum sensitivity of 542.5 deg/RIU have been achieved for Ag with a thickness of 50 nm deposited on CaF2 prism, PtSe2 with three layers, and graphene with a single layer.

This paper presents a highly sensitive photonic crystal fiber (PCF)-based sensor for detecting varying concentrations of heavy metal ions, specifically Cu2⁺ and Mg2⁺, in water samples. The proposed PCF sensor features an asymmetrical arrangement of rectangular and square air holes in the cladding region, with a single rectangular core region at its center. The sensor is modeled and analyzed using COMSOL Multiphysics 5.6, employing the finite element method (FEM) with a perfectly matched layer (PML) boundary condition. Zeonex is used as the fiber material. Operating at 1.6 THz, the sensor achieves unprecedented relative sensitivity exceeding 99 (CL < 6.08 ×10^-14 cm^-1) and effective material loss (EML < 20.34 ×10^-4 cm^-1) demonstrate compared to existing sensors. This work bridges the gap between theoretical photonic design and environmental sensing applications, offering a cost-effective alternative to conventional detection techniques.

Breast cancer, particularly in cell lines such as MDA-MB 231 and MCF-7, remains one of the leading causes of mortality worldwide. Timely detection of these cancerous cells is crucial for saving lives. However, existing detection systems often face challenges, including high costs, limited sensitivity, and prolonged processing times. To address these limitations, this study introduces a novel surface plasmon resonance sensor that offers a cost-effective, rapid, and accurate sensing capability. The proposed sensor employs a high-efficiency design based on perovskite (PVK) integrated with graphene layers. The nanostructure comprises a prism (PS)/Ag/TiO₂/PVK/graphene/sensing medium (SM). The results demonstrate that the SPR sensor with the PVK layer significantly outperforms conventional designs without the PVK layer. Furthermore, optimization of the Ag, PVK, TiO₂, and graphene layer thicknesses yielded superior performance, achieving sensitivities of 363.57°/RIU and 377.85°/RIU for MDA-MB 231 and MCF-7 cells, respectively. These sensitivities were achieved using 60 nm of Ag, 2.5 nm of TiO₂, 2 nm of PVK, and one graphene sheet (G = 1). Overall, the proposed SPR sensor structure presents a highly promising approach for developing next-generation, highly sensitive biosensing tools in cancer diagnostics.

Proteins are essential for tissue construction and repair, underscoring the importance of creating a sensitive biosensor for rapid determination of protein concentrations in aqueous solutions. Here, a surface plasmon resonance (SPR)-based biosensor consisting prism (BK7), silver (Ag), titanium dioxide (TiO2), and graphene layers is theoretically proposed and numerically investigated for the determination of protein level in an aqueous solution. The numerical findings demonstrate that the suggested sensor has an enhanced sensitivity than the conventional one without titanium dioxide. Silver (Ag), titanium dioxide (TiO2), and graphene layer thicknesses have been optimized for the best performance. With the improved widths of Ag (50 nm) and TiO2 (3 nm) and with three sheets of graphene, an utmost sensitivity of 280.37 deg./RIU is gotten. This performance of the suggested detector is high compared to other latest works in SPR sensing. The impressive performance of the suggested SPR-based biosensor makes it promising for application across various biosensing domains.

Industrial and technological developments cause a noteworthy rise in water adulteration with heavy metal ions. As a result, the discovery of these hazardous ions has taken substantial consideration by several physical and chemical systems. Conversely, these systems are undergoing from the high cost, difficult equipment, complicated chemical processes and time-consuming despite their relatively low detection limits and high sensitivity. Recently, angular examinations have been most commonly employed to compute sensitivity of OSPRDs. The proposed OSPRD combines ferromagnetic nickel (Ni) layer, and Al2O3 as a defensive film, and two-dimensional (2D) hetero-structure material (blue phosphorous (BlueP)-tungsten di-selenide (WSe2)). The worked wavelength for the suggested OSPRD is 633 nm. The analytical manipulation has been implemented by Mathematica 5.3 software in this article. At optimum case, the proposed OSPRD consists of 10 nm Al2O3, 60 nm Ag, and a single layer of BlueP/WSe2 which improve the sensitivity 298.55°/RIU. Thus, the advised structure provides great support to develop the efficiency as contrasted to the traditional detector for biomedical and chemical fields.

Proteins play a crucial role in tissue formation and repair, making their accurate detection essential for biomedical applications. This study presents a square-core photonic crystal fiber sensor (SCPCFS) designed for the sensitive detection of protein concentrations in aqueous solutions. Zeonex is selected as the background material due to its superior optical characteristics in the terahertz (THz) frequency range. Operating within the 0.8–2.2 THz band, the sensor achieves high relative sensitivity at 1.6 THz, with values of 97.667

Dengue virus (DeVs) is one of the most widespread and dangerous viruses. Early discovery is crucial to help in treatment of the DeVs illness. Currently, the traditional approaches for detecting DeVs infection have a lot of limitations like length of time and complexity. As a result, the scientists and engineers work hard on designing steadfast, quick, simple, low-cost, and highly insightful systems to sense of DeVs. This work introduces an optical surface plasmon resonance sensor (OSPRS) for rapid diagnosis of DeVs. The hybrid configuration of OSPRS involves silver (Ag) and nickel (Ni) inserted between titanium dioxide (TiO2) and black phosphorus (BkP) layers. The investigations of the OSPRS have been performed by Mathematica software with help of the transferee matrix approach (TMA). The thicknesses of OSPRS layers are inspected and studied to get the best efficiency. The uppermost sensitivity is reached as 299.42 deg∕RIU with 45 nm of Ag, 2 nm of TiO2, 5 nm of Ni, and 4 sheets of BkP. Also, the OSPRS has unique strengths like fast response, simple structure, and tumble design. As a result, the advised OSPRS can be employed effectively for diagnosis of the infected blood components by DeVs.

A super-wideband solar energy absorber (SWBSEA) design is proposed in this research. In order to achieve high absorption in the design, a thin film of graphene is also used as a substrate coating that is exposed to the medium of air. The metal-insulator-metal (MIM) is designed with a Ti-SiO2-TiN structure. The fractal interwoven shape (FIS) resonator layer is constructed of titanium material, which is based on a layer of silicon dioxide, and a ground layer of titanium nitride. The spectrum of solar radiation that is typically absorbed spans from the Ultraviolet (UV) to Mid-infrared (MIR) range, with 92.81% average absorption. The absorption bandwidth of 0.61 mu m is achieved with 96.21% average absorption. The designed solar absorber has a wide angle of incidence ranging from 0 degrees to 80 degrees. The design is also polarization insensitive for Transverse Electric (TE) and Transverse Magnetic (TM) waves. The created SWBSEA solar absorber design is extremely effective, polarization, and angle-insensitive, and offers broadband absorptance that may be put into the solar cell as an absorber and is frequently utilized in heating, drying, and photovoltaic applications.

To ensure good water quality, microbiological contamination in water must be detected. This process is made easier and more distinctive using a photonic crystal fiber (PCF), which offers outstanding optical sensing capabilities. Herein, a PCF sensor model is proposed for detecting two types of waterborne bacteria, namely, Vibrio cholera and Escherichia coli bacteria. The core region of the proposed PCF sensor is made up of a single rectangle and the cladding region has 32 rectangular air holes that have the same height and width as the core rectangle. Zeonex is employed as the fiber material. Using Comsol 5.6 which is based on the finite‐element method, the model is numerically analyzed and structured. The simulation verifies the effectiveness of the proposed PCF to detect the analyte samples. Numerous performance indicators are calculated at an operating 2.8 THz. Simulation results show that the proposed PCF sensor is promising. Extremely high relative sensitivity (97.996%), lower effective area (6.3575 × 10 4 μm 2 ), higher numerical aperture (0.23319), lower effective material loss (0.0034 cm −1 ), and lower confinement loss (0.1 × 10 −14 ) are obtained which indicate an efficient PCF sensor. Additionally, the simplicity of the PCF design ensures the fabrication possibilities of the proposed sensor.

This study uses an angle interrogation approach to propose an SF11 Prism- Ag- ZnO nanowires-CeO2-Sensing layer-based surface plasmon resonance sensor. The proposed multilayer structure has been used for the concentration measurement of dopamine in human blood. The thicknesses of the ZnO nanowire (ZnO-NW) and cerium oxide (CeO2) layer have been taken as 50 nm and 0.5 nm, respectively, and the thickness of the metal layer is 50 nm considered. The characteristics and parameters are also measured for the proposed sensor. The sensitivity, full width at half maximum (FWHM), detection accuracy (DA), and quality factor (QF) are obtained as 95 deg/RIU, 14.34 deg, 0.06578 deg-1, and 6.24 RIU-1, respectively. Numerous neurological illnesses are brought on by abnormalities of dopamine (D. A.), a crucial neurotransmitter in the brain's neural circuits. Quick and sensitive sensors for D. A. detection are needed to diagnose these illnesses early. The significance of this sensor in the biomedical field.

In this work, we study the propagation of optical solitons in a tapered optical fiber with attenuating effects under the effect of erbium dopants. Through the constructed Lax pair, two soliton solutions are obtained with the aid of Darboux transformation. Using Mathematica tool, obtained two soliton solution is graphically represented as 2D and 3D plots. The generated two solitons are manipulated through some dispersion profiles with attenuating effects. Results are meaningful to understand the propagation of optical soliton in the concept of lossy optical medium. Moreover, the proposed approach can be used to control the soliton with lossy effects via dispersion management scheme. Our results reveals that the changes of the soliton width, amplitude, and phases are potentially influenced by the variable coefficients particularly dispersion parameter. The GVD profile mainly affects the intensity of optical solitons which leads to control the attenuation due to absorption of optical medium. These results will be helpful to understand the dynamics of attenuated soliton transmission in an inhomogeneous optical fiber medium.

Today, a lot of attention in the zone of surface plasmon resonance-based sensors (SPRBSs) due to the current laboratory analytical devices are needed extensive quantity of time and cost and their generally operating is difficult. SPRBSs are promising devices due to they have small size, high angular sensitivity, simple structure, and low cost. Simple of production, cost-effectiveness, and disposability are some of the qualities of polymers that obtain them encouraging candidates for SPRBSs. Here, SPRBS comprises of BK7 prism, silver (Ag), polymer, black phosphorus (BPP), and sensing medium (SM). The reflectance profiles (RFPs) of the SPRBS are inspected when the SM is BSA or glucose. To boost the angular sensitivity (AS), the width of the Ag and polymer films and the quantity of BPP sheets are inspected. The highest sensitivity of 271.92 deg./RIU is achieved for 25