Plasmon Resonances within the Effective Susceptibility Concept: From Electrodynamics to Biological Applications

The description of resonance processes in nanoplasmonic structures within the framework of the electrodynamic Green's functions method and the concept of effective susceptibility is considered. This paper offers a unified perspective on plasmon resonance in spatially confined nanostructures and formulates the idea of dispersion relations in these systems. The local field enhancement effect is discussed as a resonant phenomenon. The concept of configurational resonances and its application in contemporary biology is also explored. Finally, the study examines surface plasmon resonance and its use in advanced sensor technology, with a specific focus on the in situ observation of biospecific interactions, such as those of an antigen-antibody type