Quantum Physics
Coherent multi-flavour spin dynamics in a fermionic quantum gas
7 March 2012
Photo: AG Sengstock
We demonstrate the first experimental realization of a well‐controlled fermionic spinor gas with interaction‐driven spin oscillations. By properly choosing the initial spin states we can change the effective length of the atomic spin from 1/2 to 9/2. The control over the magnetic field allows to initialize and stop spin dynamics and to select the number of involved levels. We extract the microscopic interaction parameters and find excellent agreement with a two particle model including all spin‐dependent interactions. By tuning the depth of the optical lattice, we investigated the transition from on‐site dominated to quantum manybody spin dynamics, where spins diffuse throughout the lattice producing highly entangled states. For this case, we observe a new form of melting of a band insulator.