ABSTRACT
The study of light–matter interaction via surface plasmon polaritons (SPPs) or surface plasmons (SPs) is known as plasmonics. SPs are mutual vibrations of free electrons at a metal surface that are optically stimulated. SPPs are quanta of collective charge density oscillations that are strictly restricted at the boundary of negative and positive permittivity materials. Light interaction with nanoscopic matter has been seen for eras, such as in the stained-glass goblets of the Roman Empire or magnificent medieval cathedral windows. Photonics, biological imaging, molecular spectroscopy, and sensing, to mention a few, have all benefited from the advancement of nanoplasmonic technology during the previous decade. The metal-insulator-metal waveguide configuration is among the most frequently utilized plasmonic-based n-structures for the development of dense optical circuits. Metal-insulator-metal waveguides are plasmonic structures with two metal claddings around an insulator. Researchers have studied the construction of a wide range of devices utilizing metal-insulator-metal waveguides to build highly integrated optical circuits.
