Ugo Fano and Shape Resonances

TL;DR

This paper reviews Ugo Fano's pioneering work on quantum interference effects, particularly Fano resonances, highlighting their significance in understanding shape resonances and their impact across various modern physical phenomena.

Contribution

It clarifies the origin and importance of Fano resonances, emphasizing their role in quantum physics and their relevance to recent discoveries in multiple fields.

Findings

Fano's prediction of quantum interference effects in photoabsorption.

Theoretical understanding of shape (Fano) resonances.

Fano resonances underpin new phenomena in diverse physical systems.

Abstract

Ugo Fano has been a leader in theoretical Physics in the XX century giving key contributions to our understanding of quantum phenomena. He passed away on 13 February 2001 after 67 years of research activity. I will focus on his prediction of the quantum interference effects to understand the high-energy photoabsorption cross section giving the Fano lineshapes. The Fano results led to the theoretical understanding of shape resonances (known also as Feshbach resonances) that should be better called Fano resonances. Finally I will show that today this Fano quantum interference effect is behind several new physical phenomena in different fields.