Atom jumping
Figure 5. A fluctuating potential can increase the atom's velocity, while the cavity-mediated friction force decreases its velocity. In this case, an atom can leave an antinode (indicated by the horizontal lines), fly along the cavity axis and be recaptured by another antinode. According to our simulation at the MPQ, this particular atom has flown across two consecutive antinodes. Before and after the flight, the trapped atom oscillates rapidly around the relevant antinode. Evidence for long atom flights is obtained from periodic bursts of photons observed in the light transmitted through the cavity.