Spectroscopic observation of SU(N)-symmetric interactions in Sr orbital magnetism

Understand

SU(N) symmetry can emerge in a quantum system with N single-particle spin states when spin is decoupled from inter-particle interactions.

• So far, only indirect evidence for this symmetry exists, and the scattering parameters remain largely unknown.
• Here we report the first spectroscopic observation of SU(N=10) symmetry in Sr-87 using the state-of-the-art measurement precision offered by an ultra-stable laser.
• By encoding the electronic orbital degree of freedom in two clock states, while keeping the system open to 10 nuclear spin sublevels, we probe the non-equilibrium two-orbital SU(N) magnetism via Ramsey spectroscopy of atoms confined in an array of two-dimensional optical traps.