Pauli blocking enhanced life-times and cooperative radiation in a 2D Fermi gas

The observation of Pauli blocking of atomic spontaneous decay via direct measurements of the atomic population requires the use of long-lived atomic gases where quantum statistics, atom recoil and cooperative radiative processes are all relevant. We develop a theoretical framework capable of simultaneously accounting for these effects and apply it to atoms featuring an effective $\Lambda$ level structure confined in a single 2D pancake or arrays of pancakes. We identify a parameter window in which a factor of two extension in the atomic lifetime clearly attributable to Pauli blocking should be experimentally observable in deeply degenerate gases with $\sim 10^{3} $ atoms. Consistent with these theory predictions, we experimentally observe a $\sim$20\% suppressed excited state decay rate in the moderately degenerate regime on the ${}^{1}\rm{S_0}-{}^{3}\rm{P_1}$ transition in $^{87}$Sr atoms.

Ref: arXiv:2108.02819