Ram Bharos Yadav

For enhanced sensitivity, a theoretically designed surface plasmon resonance (SPR)-based gas sensor employing a BK7 prism, silver (Ag), nickel–zinc ferrite oxide (Ni[ ]Zn[ ]Fe₂O[ ] and zinc oxide (ZnO) is proposed using the Kretschmann configuration. In order to detect a wide range of gaseous analytes, this sensor architecture makes use of the high field confinement and charge transfer properties at the metal–dielectric interfaces. The gas sensor performance parameter is computed using the angular interrogation method in terms of sensitivity, detection accuracy (DA), and figure of merit (FoM). The maximum sensitivity of the suggested gas sensor is found to be 222.51[ ]/RIU below 0.3 (a.u.) at [ ] with remarkable FoM. The simulation results indicate that the proposed sensor achieves a maximum sensitivity of 222.51[ ]/RIU at a minimum reflectance of below 0.3 (a.u.), along with a high FoM, signifying its superior detection capability compared to conventional SPR gas sensors. The outcomes of our enhanced numerical analysis demonstrate that performance is enhanced when compared with a traditional gaseous sensor. Additionally, for the detection of NO₂ gas, the maximal sensitivity of 245.58[ ]/RIU is attained, demonstrating the sensor’s strong potential for selective and precise gas detection. Furthermore, the suggested gas sensor can identify gas analytes with different RI. Therefore, using a BK7 prism with the suggested gas sensor can be more effective for detecting various gases at 633[ ]nm wavelengths.

We report growth and characterization of n-Si/p-SnO _x heterojunction using RF sputtering for deposition of p-type SnO _x under controlled growth oxygen pressure over n-type silicon (Si) wafer. The heterojunction properties of Si/SnO _x were varied by controlling the growth oxygen pressure of SnOx. Several characterization techniques, including PL (photoluminescence), AFM (atomic force microscopy), FESEM (field emission scanning electron microscopy), XRD, I-V characteristics and Hall measurement, were conducted to analyze the structural, optical, and electrical properties of the n-Si/p-SnOx heterojunction. The knee voltage (V _knee ), or cut-in voltage, was calculated by analyzing the gradient of the dark current-voltage (J-V) curves when the bias was applied in the forward direction. The V _knee values for type-I, type-II, and type-III n-Si/p-SnO _x heterojunctions were determined to be 0.62 V, 0.84 V, and 1.0 V, respectively. The ideality factors (n ₁ and n ₂ ) were determined to be 1.52, 2.22, 3.52, and 8.41, 9.31, 10.34, respectively, for various heterojunction types. The reverse saturation current densities, J ₀₁ and J ₀₂ ranging from approximately 10 ⁻⁷ to 10 ⁻⁶ A/cm ² , and 10 ⁻⁵ to 10 ⁻⁴ A/cm ² , respectively. The objective of this experimental work is to investigate especially, the prospect of silicon /metal-oxide (Si/SnOx) based heterojunction to be used as optical sensors with tunable optoelectronic properties of SnOx.

In this paper, a TMDC-based surface plasmon resonance (SPR) sensor for detecting fat concentration milk, incorporating an Ag-Pt (bimetallic) layer, is presented. The Pt (Platinum) layer provides chemical stability and increases sensitivity with the TMDC layer. Compared to the conventional SPR sensor, the maximum sensitivity, detection accuracy (DA), and figure of merit (FoM) of 314^∘/RIU, 0.142/degree, and FoM 44.05/RIU are achieved with the WS₂ layer. The sensor’s increased sensitivity is due to the increased field intensity and depth of penetration into the sensor layer, resulting in a larger interaction volume. The presence of the WS₂ layer, with its significant imaginary part of the dielectric constant, helps improve sensitivity and broadens the SPR curves. This broadening SPR curve ultimately affects the DA and FoM of the sensor. The capability of the proposed sensor to detect various biological analytes with a refractive index (1.3452–1.3657) can be demonstrated.