Ultracold atoms in optical lattices with random on-site interactions.
We consider the physics of lattice bosons affected by disordered on-site interparticle interactions. Characteristic qualitative changes in the zero-temperature phase diagram are observed when compared to the case of randomness in the chemical potential. The Mott-insulating regions shrink and eventually vanish for any finite disorder strength beyond a sufficiently large filling factor. Furthermore, at low values of the chemical potential both the superfluid and Mott insulator are stable towards formation of a Bose glass leading to a possibly nontrivial tricritical point. We discuss feasible experimental realizations of our scenario in the context of ultracold atoms on optical lattices.
Gimperlein
H
H
Institut für Theoretische Physik III, Universität Stuttgart, Pfaffenwaldring 57 V, D-70550 Stuttgart, Germany.
Wessel
S
S
Schmiedmayer
J
J
Santos
L
L