Destructive interference between opposite time orders of photon emission
C. A. Schrama, Gerard Nienhuis, H.A. Dijkerman, C. Steijsiger, H G M Heideman · Physical Review Letters · 1991
We predict that the intensity correlation between the Rayleigh line and a sideband of the fluorescence triplet displays destructive interference between opposite time orders of photon emission. We have measured this effect in natural barium. To our knowledge such an interference effect has not been observed before in atomic physics.