Entanglement, identity, and disentanglement in two-atom spontaneous emission

Two recent experiments studying the potential effect of entanglement on the emission properties of excited atoms produced in molecular photodissociation have been interpreted in conflicting ways. We present a theoretical analysis of the problem, showing that the experimental results can be explained by a combination of three processes: entanglement, exchange effects associated with the identical nature of the atoms, and disentanglement by spontaneous emission. According to our approach these experiments provide a verification of the phenomenon of disentanglement by spontaneous emission.

Figure 1

Temporal dependence of the normalized number of detections per unit time of photons at each detector ($n_i$; $i=1,2$; black line), first photons ($n_f$; blue line), and second photons ($n_s$; red line). The time and detection numbers are represented in units of ${\mathrm{\Gamma }}^{-1}$ and $\mathrm{\Gamma }$, respectively, with ${\mathrm{\Gamma }}^{-1}=1.6{10}^{-9}$ s.