Electro-Ionic Control of Surface Plasmons in Graphene-Layered Heterostructures.

Precise control of light is indispensable to modern optical communication devices especially as the size of such devices approaches the subwavelength scale. Plasmonic devices are suitable for the development of these optical devices due to the extreme field confinement and its ability to be controlled by tuning the carrier density at the metal/dielectric interface. Here, an electro-ionic controlled plasmonic device consisting of Au/graphene/ion-gel is demonstrated as an optical switch, where an external electric field modulates the real part of the electrical conductivity.

Au nano-urchins enabled localized surface plasmon resonance sensing of beta amyloid fibrillation.

Early stage detection of neurodegenerative diseases such as Alzheimer's disease (AD) is of utmost importance, as it has become one of the leading causes of death of millions of people. The gradual intellectual decline in AD patients is an outcome of fibrillation of amyloid beta 1-42 (Aβ) peptides in the brain. In this paper, we present localized surface plasmon resonance (LSPR) based sensing of Aβ fibrillation using Au nano-urchins.

(CuO-Au) - Graphene - Au layered structures as efficient near Infra - Red SERS substrates.

Near Infra-Red Surface Enhanced Raman Spectroscopy (NIR SERS) has gained huge attention in recent years as the conventional visible SERS suffers from overwhelming fluorescence background from the fluorophore resulting in the masking of Raman signals. In this paper, we propose a novel multi-layered SERS substrate- (CuO - Au) - Graphene - Au - for efficient NIR SERS applications. The proposed structure has a monolayer of CuO - Au core-shell particles on a Au substrate with 1 nm thick graphene spacer layer.

Femtosecond laser-pumped plasmonically enhanced near-infrared random laser based on engineered scatterers.

In this Letter, we report on the design, fabrication, and implementation of a novel plasmon-mode-driven low-threshold near-infrared (NIR) random laser (RL) in the 850-900 nm range based on plasmonic ZnS@Au core-shell scatterers. Plasmon modes in the NIR region are used for nanoscale scatterer engineering of ZnS@Au core-shell particles to enhance scattering, as against pristine ZnS. This plasmonic scattering enhancement coupled with femtosecond (fs) laser pumping is shown to cause a three-fold lasing threshold reduction from 325  μJ/cm to 100  μJ/cm and a mode Q-factor enhancement from 200 to 540 for ZnS@Au-based RL, as compared to pristine ZnS-based RL.