Precision Spectroscopy of an Interacting Ytterbium Fermi-Fermi Mixture

We study an ultracold interacting Fermi-Fermi mixture of $^{171}$Yb and $^{173}$Yb. The Yb Fermi-Fermi mixture in the ground state is characterized by strongly attractive inter-species interactions, while the intra-species interactions are vanishing for $^{171}$Yb and repulsive for $^{173}$Yb. Performing precision spectroscopy on the $^{1}$S$_{0}$ to $^{3}$P$_{0}$ clock transition we find and characterize a SU($\it{2}$) $\times$ SU($\it{6}$) symmetric interspecies interorbital interaction. We discuss prospects of spectroscopic methods to gain information on the many-body state of the system.