Molecular photon echoes as a signature of vibrational cat states
  Quantum interference between two distinct vibrational trajectories induced by two pulse femtosecond excitation in molecules is shown to result in a photon echo, providing direct evidence of the cat state superposition of Gaussian vibrational wavepackets. 
Holger F. Hofmann, Takao Fuji, Atsushi Sugita, and Takayoshi Kobayashi