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In this article, an optical bio-chemical sensor based on D-shaped optical fiber is presented for ethanol detection application. The gold and graphene nanolayers are coated for inducing the SPR over an optical fiber flat surface. The molecularly imprinted polymer (MIP) thin film is also coated over the gold film to enhance the molecular interaction between the sensing fluid and the sensing surface. The ethanol concentration is detected with reference to the 0% concentration and increased to 90% in a sample solution. The shift in resonance wavelength detects the concentration of the ethanol in the fluid sample due to the change in RI. The result shows a very good agreement between the concentration of ethanol in fluid and the resonance wavelength (RW) shift. The maximum obtained average sensitivity is 2.5 nm/concentration (every 10%) or 714 nm/RIU with Au/MIP thin film and 1137 nm/RIU for graphene/Au/MIP thin film. Based on the result and optical properties of the proposed sensor, it might be used as a real-time alcohol detector. This sensor can protect foods and drinks from the imbalance of chemicals and preservatives. [ABSTRACT FROM AUTHOR]

This article presents a highly sensitive gold/Ti 3 C 2 T x coated photonic crystal fiber (PCF)-based surface plasmon resonance (SPR) sensor for cancer cells detection. The hybrid gold/Ti 3 C 2 T x layer is coated circularly over PCF for occurrence of SPR by coupled mode theory. The simulations and numerical analysis are done by the finite element method. The resonance wavelength shift is measured between normal and cancerous cell samples to estimate the wavelength sensitivity and resolution. In results, the maximum wavelength sensitivity for breast cancer MCF-7 cells is achieved as 10,714 nm/RIU in x-polarization mode and 13,071 nm/RIU in y-polarization mode with very low resolution of 10−6 RIU. The impact of the MXene (Ti 3 C 2 T x) thin film on sensitivity is also observed. In addition, the optimization of parametric variation is analyzed with machine learning technique with low mean squared error of 0.01525. <2% error is obtained in sensitivity analysis with multilayer perceptron regressor. Due to the advanced results and machine learning application, this sensor can be used as a fast, efficient and low-cost cancer disease detection device. [Display omitted] • A gold/Ti 3 C 2 T x coated PCF based SPR sensor is presented and numerically analyzed for detecting various cancer cells. • Vertical confinement path is used to transform the energy from core mode to SPR mode with external sensing approach. • The normal to cancerous cell is detected by measuring the corresponding resonance wavelength shift. • The Multilayer Perceptron regressor has been employed on ANN model for predicting the output of PCF-SPR sensor. [ABSTRACT FROM AUTHOR]

In this article, an Au/Ti 3 C 2 T x MXene hybrid layered D-shaped Photonic Crystal Fiber (DPCF) based Surface Plasmonic Resonance (SPR) biosensor is proposed. The D-shape of PCF is used to make the sensor practically more feasible. The MXene-Au hybrid thin films are placed over the DPCF to induce the surface plasmon polariton (SPP). The resonance wavelength shift occurs when analytes refractive index (RI) is changed. The numerical analysis has been performed by finite element analysis. The results have shown the wavelength sensitivity of 7000 nm/RIU and 13,000 nm/RIU for MXene layer thickness of 14 nm and 27 nm respectively. On comparing, it has been observed that the MXene/Au layered sensor has achieved 3.5 to 6.5 times higher wavelength-sensitivity compared to without MXene thin film. In addition, sensing parameters like resolution, amplitude sensitivity and figure of merit has also been investigated. The proposed sensor is used for sensing the analytes having RI range of 1.33–1.39. The range of RI covers most of the blood cells compositions, cancerous cells, protein and viruses. Therefore, this study can facilitate the use of MXene material with D-shaped PCF to detect the biochemical and chemical liquids. Photonic crystal fiber, MXene material, Gold, Surface plasmon resonance, Biomolecules. • A surface plasmon resonance sensor based on D-shape of PCF is proposed using Mxene/Au material thin film for the first time. • The sensing analytes having a refractive index (RI) range of 1.33–1.39 are used. The range of RI covers most of the bio analyte's RI like blood cells, cancerous cells, RNA/DNA, malaria-infected RBCs, protein and viruses. • The results show the wavelength sensitivity of 7000 nm/RIU and 13,000 nm/RIU for Mxene layer thickness 14 nm and 27 nm respectively. • On comparing, it has been observed that the Mxene/Au layered sensor has 3.5 to 6.5 times higher wavelength-sensitivity than without the Mxene thin layer. • The effect of the Mxene layer on other sensing parameters like resolution, amplitude sensitivity and figure of merit has also been investigated. [ABSTRACT FROM AUTHOR]

• Novel third-generation Ovonic memory materials have been synthesized. • Observed the significant electrical switching in thin-film samples. • Correlation between thermal stability and threshold switching voltage has been found. • Meyer-Neldel rule is observed in both d.c. conduction and resistive switching. The objective of the present research is to investigate the consequences of the incorporation of a small amount of Cd on the electrical switching behavior at high electric field 104 V/cm in Se 78-x Te 20 Sn 2 Cd x (x = 0, 2, 4, and 6) thin films. The thermal evaporation method has been utilized for thin-film deposition on a highly polished pyrographite substrate. The current-voltage (I-V) characteristics for the thin films of the examined samples exhibit a resistive switching of memory-type. The effect of ambient temperature and Cadmium content on the switching characteristics and voltage has been studied. The exponential decay in the observed average value of the switching voltage (V th) is found with the rise in temperature and Cd addition as well. An endeavor had been done to study the observed compositional dependence in terms of the thermal-induced glass transition temperature (T g), thermal stability, chemical bond approach, and lone-pair electrons (LP). On metal addition (Cd), the threshold voltage, glass transition temperature, and lone-pair electrons decrease while the chemical order network increases by the increase of the Cd-Se homopolar bonds. The switching phenomenon in amorphous Se 78-x Te 20 Sn 2 Cd x (0 ≤ x ≤ 6) thin films is elucidated according to an electro-thermal model based on the Joule-heating effect. [Display omitted] [ABSTRACT FROM AUTHOR]