Fano Resonance in Atoms

Fano resonance occurs when a discrete energy state within an atom interacts with a continuum of nearby states, leading to characteristic asymmetric spectral features. This phenomenon arises from quantum interference between the direct transition to the continuum and the transition via the discrete state. As a result, instead of a simple peak or dip in the absorption or emission spectrum, there's a distinctive asymmetric shape. Fano resonances reveal details about the interaction between localized and delocalized electronic states and are observed in various systems, including atoms, molecules, and nanostructures, providing insights into their underlying quantum dynamics.