Abstract
We present photoexcitation of ultra-long-range Rydberg molecules as a probe of spatial correlations in bosonic and fermionic quantum gases. Rydberg molecules can be created with well-defined internuclear spacing, set by the radius of the outer lobe of the Rydberg electron wave function . By varying the principal quantum number of the target Rydberg state, the molecular excitation rate can be used to map the pair-correlation function of the trapped gas . We demonstrate this with ultracold Sr gases and probe pair-separation length scales in the range , which are on the order of the thermal de Broglie wavelength for temperatures around 1 . We observe bunching for a single-component Bose gas of and antibunching due to Pauli exclusion at short distances for a polarized Fermi gas of , revealing the effects of quantum statistics.
- Received 26 March 2019
DOI:https://doi.org/10.1103/PhysRevA.100.011402
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