We report on the first direct observation of fast spin-exchange coherent oscillations between different long-lived electronic orbitals of ultracold $^{ 173}$Yb fermions. We measure, in a model-independent way, the strength of the exchange interaction driving this coherent process. This observation allows us to retrieve important information on the inter-orbital collisional properties of $^{ 173}$Yb atoms and paves the way to novel quantum simulations of paradigmatic models of two-orbital quantum magnetism.
Categories: cond-mat.quant-gas physics.atom-ph quant-ph