Interaction time of two macroscopic quantum wave packets colliding with a rectangular barrier

Abstract We theoretically study the dynamical process of two macroscopic quantum wave packets colliding with a rectangular barrier. We define an interaction time as the time interval between two instants when the atomic probability reaches its maximum at the center and edges of the barrier, serving as a key quantity to characterize this collision process. The impacts of various barrier parameters and wave packet incident energies on the interaction time are systematically explored. Two interferometry schemes, namely Mach–Zehnder scheme and Hong–Ou–Mandel (HOM) scheme, are proposed to determine the interaction time, and the mappings between the interaction time and the observable quantities of the two schemes are established. Through a comparative analysis of the sensitivity of the observable quantities, it is revealed that the HOM scheme exhibits distinct advantages. This research contributes to the quantitative study of quantum tunneling and matter-wave interference, and it is anticipated that the findings can be experimentally validated.