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In this work high density ZnO nanorods were grown on glass substrate by using a two-step method. In the first step, drop-casting method was used for growth of seed layer by taking Zinc Acetate Dihydrate as precursor. In the second step, ZnO nanorods were prepared through Chemical Bath Deposition process on this seed layer by taking Zinc Nitrate as precursor. Field Emission Scanning Electron Microscope study was done to study the morphology of grown ZnO nanorods. From this study the average diameter and length of nanorods were found to be 33 nm and 270 nm respectively. These nanorods are successfully used for second harmonic generation (SHG) of femtosecond laser pulses of central wavelengths like 1000 nm, 1100 nm and 1300 nm. Discussion is given on the significance of this result along with its potential application. [ABSTRACT FROM AUTHOR]

The objective of the proposed work is to design a biosensor that monitors hemoglobin (Hb) concentration using the combination of nanolayer, i.e., barium titanate (BaTiO3) and antimonene based on surface plasmon resonance (SPR) technique. Antimonene is used here as bio-recognition element (BRE) layer to attach the Hb analyte through physical adsorption due to its hydrophilic nature, higher adsorption energy and larger active surface area. The use of BaTiO3 adlayer (7 nm) just before antimonene is to enhance the refractive index (RI) sensitivity up to 1.90 times for the proposed SPR biosensor. The reason behind sensitivity enhancement is its high dielectric constant which enhances the electromagnetic field with in analyte medium. The performance of the biosensor is demonstrated with performance parameters namely sensitivity, detection accuracy (DA), figure of merit (FOM) and resolution. The proposed biosensor has potential to achieve much higher performance in terms of RI sensitivity of 303.83°/RIU, FOM of 50.39 RIU−1 and resolution of 0.021 g/l in comparison with reported biosensors in the literature for detection of Hb concentration. Thus, based on the obtained results one can say that the proposed work unlocks a reliable sensing in the field of medical science to detect hemoglobin-related diseases in human being. [ABSTRACT FROM AUTHOR]

We present a detailed design principle and propagation characteristics of a channel plasmon-photonic-crystal-coupled-waveguide (PPCCW) for realizing terahertz (THz) waveguides and waveguide-based devices. The avoided-crossing behavior exhibited by dispersion curves of the supermodes due to modal interference leads to a sharp change in group velocity close to the phase-matching wavelength. As a consequence, the group-velocity dispersion (GVD) peaks to a maxima (~1.40 × 10 ps/km·μm) and dips to a minima (~−1.60 × 10 ps/km·μm), thus exhibiting extremely large GVD. The propagation length is obtained in the order of a few centimeters. The analysis is substantiated by the frequency dependence of mode field distribution and propagation loss suffered by the supermodes of PPCCW geometry. Also, the obtained result is in good agreement with FEM-based study. The proposed waveguide is aimed at facilitating enhanced performance THz-waveguide sensors and GVD compensation modules. [ABSTRACT FROM AUTHOR]

We present an experimental study on measurement of nonlinear refractive index ( n) of organic liquids when the thermo-optic effects manifest into large nonlinear phase shifts (Δ ϕ) in an open-aperture Z-scan configuration. Although we do not obtain the familiar peak-valley normalized transmittance curve as in the case of closed-aperture Z-scan technique, we use a theoretical model using Gaussian beam decomposition (GD) technique to estimate the value of n. Using this recipe, we obtain the nonlinear refractive index n = −(4.90 ± 1.20) × 10 cm/W for toluene (organic solvent) and n = −(10.60 ± 2.10) × 10 cm/W for an organic polymer solution (10 M in toluene). By carrying out absorption measurements directly with an unfocussed Gaussian beam, we found nonlinear absorptions β = (2.42 ± 0.20) × 10 m/W and β = (2.79 ± 0.24) × 10 m/W which are close to the expected results. [ABSTRACT FROM AUTHOR]

The article reports on the tailoring of the spectral features of extraordinary transmission (EOT) through sub-wavelength periodic hole array using a distributed-Bragg-reflector (DBR). Topics discussed include the new EOT created by the photonic stop-bands and high transmission regions in the DBR spectrum, and full-vectorial two-dimensional finite difference time domain (2D-FDTD) technique.

We propose a highly sensitive temperature sensor based on photonic crystal surface plasmon waveguides comprising different plasmonic active metals such as gold, silver, and aluminum, utilizing surface plasmon resonance phenomenon. We found that the resonance wavelength can be easily and substantially tuned over a broad spectral range by changing the temperature and also by judiciously choosing the different plasmonic metals. Employing coupled mode theory, we found that the proposed sensor can be used in harsh environment with sensitivity as high as ∼70 pm/K around telecommunication window. [ABSTRACT FROM AUTHOR]