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.

Enhanced absorption in a graphene embedded 1D guided-mode-resonance structure without back-reflector and interferometrically written gratings.

A theoretical model based on the coupled mode theory is presented to calculate the absorption in a graphene embedded 1D guided-mode-resonance (GMR) structure that does not require a back reflector. The optimized graphene-GMR structure can absorb up to 70% of the incident light which far exceeds the already reported results without using any back-metal reflector or Bragg mirror. The theoretical analysis is valid for binary gratings and pyramidal gratings which are patterned using an interference lithography system.