Data and analysis for the results presented in M. A. Seidler, R. Gutiérrez-Jáuregui, A. Cerè, R. Jáuregui, and C. Kurtsiefer, arXiv:1812.00129 (2018).
We present a method to estimate the time scale of quantum jumps from the time correlation of photon pairs generated from a cascade decay in an atomic system, and realize it experimentally in a cold cloud of 87Rb. Taking into account the photodetector response, we find an upper bound for the duration of a quantum jump of 21 ± 11 ps.