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Nanomaterials are proven as suitable alternatives for invasive treatments in cancer patients to help reduce the mortality rate. Thus, incorporating oncological imaging during photothermal therapy widens the scope for hybrid plasmonic nanomaterials in a noninvasive way. We present herein the synthesis of core-multishell Au@Cu 2−x S@Au nanoparticles with dual localized surface plasmon resonance in visible and near-infrared spectral regions. The plasmonically engineered nanoparticles were used in in vitro NIR-LED-based low-intensity photothermal therapy (LI-PTT) and surface-enhanced Raman scattering (SERS)-based bioimaging. The precise temperature-induced cell apoptosis was explicitly accessed by SERS mapping after treatment. Numerical simulations were carried out on core-multishell nanoparticles to understand the electric field confinement and heat dissipation inside the nanoparticle domain. Moreover, good biocompatibility and stability of hybrid core-multishell nanoparticles make them potential candidates for possible SERS-guided LI-PTT.

Aim: To prepare efficient metal-semiconductor nanoparticles as noninvasive, real-time imaging probes for photothermal therapy (PTT) applications. Materials & methods: A bottom-up approach was used to fabricate core-shell Ag@CuS nanoparticles (NPs). PTT and Raman mapping were done using HeLa cells. Theoretical simulation of electric field enhancement and heat dissipation density of Ag@CuS NPs was performed. Results: PTT-induced hyperthermia was achieved under 940 nm near-infrared light irradiation. Surface-enhanced Raman spectroscopy (SERS) signals of dye molecules were observed when conjugated with Ag@CuS NPs. Conclusion: Ag@CuS NPs are found to be efficient for SERS imaging and localized heating under laser irradiation, making a promising candidate for SERS-guided PTT.

In this work, the high pressure phase of titanium dioxide (TiO2‐II) film is grown with vapor‐liquid‐solid (VLS) method on <100>‐GaAs substrate by utilizing the natural process‐induced‐strain, originating from the thermo‐elastic mismatch between TiO2 and GaAs in VLS process. The mismatches in thermal expansion coefficient and elastic constant of TiO2 and GaAs are Δα≈55% and ΔY≈170% which incorporate a substantial amount of stress (≈GPa) during cooling from the growth temperature (500 °C). SEM imaging suggests the formation of a continuous film and cross‐sectional TEM image confirmed its high crystalline quality. XRD peaks at 2θ = 31.300 and 58.670 confirm the formation of [111] and [212]‐planes of TiO2‐II phase and its chemical states are analyzed from X‐ray photoelectron spectroscopy (XPS) measurements. The bandgap of TiO2‐II phase is estimated to be 2.88 eV from cathodoluminescence study for the first time which agrees satisfactorily with the theoretical predictions reported.

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A wide band optimized H-slot microstrip antenna is described in this paper. The radiating patch is mounted upon a dielectric substrate and the antenna is excited by a microstrip line feed. The antenna dimensions and the radiation parameters such as return loss, VSWR, gain and directivity are studied using Ansoft HFSS. Particle Swarm Optimization (PSO) which is an effective evolutionary optimization technique is used for optimizing the proposed antenna. This method provided better results in the design of the antenna and it also analyzed the effect of the various design parameters like substrate length and height, length of the patch and feed. The improvement in the results has been included in the design. Therefore, with the modified parameters, the antenna exhibits 50% increase in bandwidth which is shown in the results section.

The current work proposes a novel technique to incorporate process-induced uni-axial stress for significant mobility boosting in high-performance metal-oxide-semiconductor field-effect-transistors. It has been shown that two existing standard techniques, namely, silicon-on-sapphire and high-k gate dielectrics can be combined to develop such technology. Sapphire has very high elastic constant and thermal expansion coefficient, thereby capable of inducing a significant amount of stress which is observed to be biaxial in nature. However, with the incorporation of different materials during process integration, such biaxial stress is gradually changed to uni-axial nature. The high-k gate dielectric plays the key role in converting the biaxial stress to uni-axial. Several high-k gate dielectrics have been studied and titanium oxide (TiO 2 ) is observed to maximize the induced stress and also effective to convert it to uni-axial. A final average longitudinal channel stress of 0.73 GPa has been obtained.