Pauli blocking of atomic spontaneous decay
Dr. Christian Sanner (JILA, University of Colorado, Boulder, USA)

Can Fermi quantum statistics be used to manipulate the radiative properties of atomic emitters? Is it possible to extend the natural lifetime of an electronically excited atom by placing it inside a bath of quantum-degenerate ground-state atoms? I will report on an experiment that demonstrates how a Fermi sea can block the spontaneous decay of an excited atom. This striking manifestation of Fermi statistics connects for the first time the fundamental radiative property of atoms to their motional degrees of freedom subject to quantum statistics. Quantum engineering the atom-photon coupling opens up new perspectives for optical clocks, which face spontaneous decay as a fundamental decoherence mechanism.