Plasmonics attract significant attention of the researchers due to Plasmon’s surpassing ability to match free space electromagnetic (EM) excitation into the nano-scale size and conduct the light-tissue interaction in this scale. Plasmonic nano-antennas (PNAs) is a coupling of EM waves into Localized Surface Plasmon Resonance (LSPR) which is considered as an interesting subject for theoretical and experimental study. This presents a new concept of the confinement of light in subwavelength scales with huge local fields which can generate very high near field intensities because of their LSPR. The generated field is invested in various applications that are depending on near field enhancement produced by plasmonic optical nano-antennas (PONAs) such as Surface-Enhanced Raman Spectroscopy (SERS), biosensing, spectral imaging and cancer treatment. Bowtie shape PNAs (PBNAs) can transfer the light field efficiently by converting the light from external space into a subwavelength spectral region with the improvement at an optical wavelength in a tiny area between its antenna arms. The local EM field production in a gap area is the main reason to suggest PBNAs shape if the frequency of the incident EM waves coincide the structural resonance peak so it is acting as a tunable hot spot.
Part of the book: Plasmonic Nanostructures