N-body antibunching in a degenerate Fermi gas of 3He∗ atoms

A key set of observables for investigating quantum systems are the n-body correlation functions, which provide a powerful tool for experimentally determining coherence and directly probing the many-body wave function. While the (bosonic) correlations of photonic systems are well explored, the correlations present in matter-wave systems, particularly for fermionic atoms, are still an emerging field. In this work, we use the unique single-atom detection properties of He∗3 atoms to perform simultaneous measurements of the n-body quantum correlations, up to the fifth order, of a degenerate Fermi gas. In a direct demonstration of the Pauli exclusion principle, we observe clear antibunching at all orders and find good agreement with predicted correlation volumes. Our results pave the way for using correlation functions to probe some of the rich physics associated with fermionic systems.