We deterministically prepare quantum states consisting of few fermions in single and double-well potentials. A new imaging scheme for fermionic Lithium allows us to detect correlations in the quantum states on a single-atom level and with spin resolution.
Our detection method is based on fluorescence imaging. With a high-resolution objective we image about 15 scattered photons per atom on an EMCCD camera.
This is sufficient to identify and locate single atoms in our imaging plane.
We can perform this scheme in situ or after an expansion in time-of-flight and additionally resolve the spin by subsequently adressing the different hyperfine states.
We use this technique to measure the two-point momentum correlations in deterministically prepared quantum states. In this way, we can probe the spatial symmetry of the two-particle wavefunction and investigate the emergence of momentum correlations of two repulsive fermions in the ground state of a double-well potential. The high contrast and the scalability of the detection technique allows us to go beyond measuring two-point correlations and characterize many-body quantum states.