Louis Lafforgue (University of Innsbruck)
Control and Scattering Properties in Dipolar Spin Mixtures
Lanthanides, such as erbium and dysprosium, have emerged as valuable resources in quantum-gas science. Among many interesting properties, like their strong magnetic dipole-dipole interactions and their rich optical spectrum, they are known for their large spin manifold in the ground state. To utilize these characteristics, precise control of the spin population and a thorough understanding of the underlying collision processes is needed.
Here, I will present a novel method for manipulating the spin population in bosonic erbium by using a laser tuned to a clock-like transition present in erbium at 1299nm. By applying a sequence of Rabi-pulse pairs we can climb the ladder of Zeeman sublevels and prepare arbitrary superpositions of spin states. This allows us to record Feshbach resonance spectra of various spin mixtures to investigate spin-dependent scattering processes. We observe a series of Fano-shaped resonances in the atom number spectra, showing regions where inelastic collisions are reduced by an order of magnitude. We model our system with a multi-channel square-well model and find good agreement with the experimental data. If time permits, I will show some possible implementation of advanced lattice spin models with our system.