Rodolfo Bonifacio

Rodolfo Bonifacio (1945- 2016)

Rodolfo Bonifacio was an Italian physicist who made significant contributions to the fields of optics and laser physics.

For his groundbreaking contributions, Rodolfo Bonifacio received recognition within the scientific community. In 1987, he was awarded the Michelson Medal from the Franklin Institute for his work on optical bistability, and in 1994, he received the Einstein Prize from the Society for Quantum Optics and Quantum Electronics for his pioneering contributions to Free Electron Lasers.

Bonifacio's research began during a period of rapid development in quantum and non-linear optics, coinciding with the early stages of laser technology. He collaborated with Tito Arecchi on one of his initial papers, in which they derived nonlinear equations that described the interaction between an electromagnetic pulse and a group of two-level atoms. This work laid the foundation for the Maxwell-Bloch equations, and they introduced the Slowly Varying Envelope Approximation, leading to the discovery of a hyperbolic secant π-pulse solution.

During the 1970s, Bonifacio, along with colleagues Paolo Schwendimann and Fritz Haake, formulated both classical and quantum theories of Cooperative Spontaneous Emission. He coined the term "Superfluorescence" to describe the emission from a collection of excited two-level atoms under certain conditions. This concept eventually led to the description of oscillatory superfluorescence, which was confirmed experimentally.

Together with Luigi Lugiato, Bonifacio proposed the meanfield theory of Optical Bistability in the mid-1970s, which became widely accepted in the scientific community. They also developed an exact theory of optical bistability in a ring cavity, predicting phenomena such as optical self-pulsing.

In the late 1970s, Bonifacio shifted his focus to the emerging field of Free Electron Lasers (FELs). He, along with coauthors Federico Casagrande and Giulio Casati, presented a model of a FEL that revealed chaotic behavior and cooperative radiation emission under specific conditions. His subsequent work in the 1980s and 1990s provided insights into various aspects of FEL behavior, including Self-Amplified Spontaneous Emission (SASE).

In the mid-1990s, Bonifacio explored light-matter interactions in atomic gases, bridging concepts from atomic and FEL physics. He led the development of the "Collective Atomic Recoil Laser" (CARL) theory, describing light amplification in cold atomic gases through collective atomic motion. This work extended to Bose-Einstein Condensates (BECs), leading to the observation of "Superradiant Rayleigh Scattering."

Bonifacio's research continued into the early 2000s, where he investigated high-gain Quantum FEL (QFEL) regimes involving collective electron-light interactions. His work held the potential to create compact sources of coherent gamma-ray radiation.