Observation of an Efimov spectrum in an atomic system

Autor: G. Roati, Marco Fattori, Chiara D'Errico, Matteo Zaccanti, B. Deissler, Giovanni Modugno, Stefan Müller, Massimo Inguscio, M. Jona-Lasinio
Rok vydání: 2009
Předmět:
Zdroj: Nature Physics
ISSN: 1745-2481
1745-2473
Popis: In 1970 V. Efimov predicted a puzzling quantum-mechanical effect that is still of great interest today. He found that three particles subjected to a resonant pairwise interaction can join into an infinite number of loosely bound states even though each particle pair cannot bind. Interestingly, the properties of these aggregates, such as the peculiar geometric scaling of their energy spectrum, are universal, i.e. independent of the microscopic details of their components. Despite an extensive search in many different physical systems, including atoms, molecules and nuclei, the characteristic spectrum of Efimov trimer states still eludes observation. Here we report on the discovery of two bound trimer states of potassium atoms very close to the Efimov scenario, which we reveal by studying three-particle collisions in an ultracold gas. Our observation provides the first evidence of an Efimov spectrum and allows a direct test of its scaling behaviour, shedding new light onto the physics of few-body systems.
Comment: 10 pages, 3 figures, 1 table
Databáze: OpenAIRE