Many-Body Localized Phase in Few-Body Systems

Motivated by recent progress with cold atoms in the field of many-body localization, we investigate the effect of interaction on the localization of atoms in few-body systems. We consider two cold atoms with short-range interaction in a one-dimensional disordered lattice with finite number of lattice sites. We obtain the exact time evolution of the wave function and monitor the structural properties of the system such as atom imbalance and von Neumann entropy as functions of time. In the limit of vanishing interaction we recover the few-body version of Anderson localization. Our results confirm that localized phase survives even for finite interaction strength, as we expect for the many-body localized phase.