Photonic sensing is a novel technology and accurate measurement for biosensing applications. The present work proposes a defective one-dimensional photonic crystal (1D-PC) based on Si/SiO2-layers with a central liquid-filled defect layer as a blood sugar concentration biosensor in the visible region. The transmission spectrum is calculated numerically by using the transfer matrix method. The thickness of the defect layer and incident angle are optimized to achieve the best performance of the sensor. The results show that the localization of defect mode shifts to a longer wavelength with increasing the defect layer thickness. In addition to increasing the incident angle from θ0 = 0° to θ0 = 90°, the defect peak was shifted towards the short wavelength region. The optimized value of our structure demonstrates high sensitivity for the blood sugar (S = 1100 nm/RIU) in the range of concentration 0–500 mg dl−1, more enhancement of the quality factor (3.539 × 106) and very low limit of detection (8.8 × 10−9 RIU) are achieved. Our results indicate that the proposed structure has higher performance as a blood sugar sensor than many previously reported data. Besides, the simplicity of the proposed structure makes it favorable to the industrial design using inexpensive and massive product nanofabrication techniques.

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A new optimized bowl-shaped mono-core surface plasmon resonance based cancer sensor is proposed for the rapid detection of different types of cancer affected cell. By considering the refractive index of each individual cancer contaminated cell with respect to their normal cell, some major optical parameters variation are observed. Moreover, the cancerous cell concentration is considered at 80% in liquid form and the detection method is finite element method with 2 100 390 mesh elements. The variation of spectrum shift is obtained by plasmonic band gap between the silica and cancer cell part which is separated by a thin (35 nm) titanium film coating. The proposed sensor depicts a high birefringence of 0.04 with a maximum coupling length of 66 μm. However, the proposed structure provides an optimum wavelength sensitivity level between about 10 000 nm/RIU and 17 500 with a resolution of the sensor between 1.5 × 10 −2 and 9.33 × 10 −3 RIU. Also, the transmittance variance of the cancerous cell ranges from almost 3300 to 6100 dB/RIU and the amplitude sensitivity ranges nearly between −340 and −420 RIU −1 for different cancer cells in major polarization mode with the maximum detection limit of 0.025. Besides, the overall sensitivity performance is measured with respect to their normal cells which can be better than any other prior structures that have already proposed.

This article discusses the tri‐core photonic crystal microstructure fiber for the process of simultaneous sensing for salinity and temperature of water substances. This kind of microstructure is preferred in many sensing application to scale the detection process in micrometer range. In this novel sensor, the sensitivity is calculated through coupling mechanism by tracking wavelength shift of various concentrations of salinity and temperature using finite element method. The sensible samples are in liquid and are infiltrated into the framed hollow cavity. Based on the coupling principle between silica substrate and the analyte material, the sense of the salt as well as temperature is obtained. Finally, it is noted that sensitivity of the salt level in water as 5404.9 nm/RIU for x polarization direction and 5674 nm/RIU for y polarization direction have been calculated with the temperature sensitivity of 4 nm/°C in the same water substances.

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