Delocalization of Weakly Interacting Bosons in a 1D Quasiperiodic Potential

Phys Rev Lett. 2014 Jul 25;113(4):045304. doi: 10.1103/PhysRevLett.113.045304. Epub 2014 Jul 23.


We consider weakly interacting bosons in a 1D quasiperiodic potential (Aubry-Azbel-Harper model) in the regime where all single-particle states are localized. We show that the interparticle interaction may lead to the many-body delocalization and we obtain the finite-temperature phase diagram. Counterintuitively, in a wide range of parameters the delocalization requires stronger coupling as the temperature increases. This means that the system of bosons can undergo a transition from a fluid to insulator (glass) state under heating.