Density matrix renormalization group for disordered bosons in one dimension

Sektion Physik, Universität München - Theresienstr. 37/III D-80333 München, Germany

Received: 11 January 1999
Accepted: 29 March 1999

Abstract

We calculate the zero-temperature phase diagram of the disordered Bose-Hubbard model in one dimension using the density matrix renormalization group. For integer filling the Mott insulator is always separated from the superfluid by a Bose glass phase. There is a re-entrance of the Bose glass both as a function of the repulsive interaction and of disorder. At half-filling where no Mott insulator exists, the superfluid density has a maximum where the kinetic and repulsive energies are about the same. Superfluidity is suppressed both for small and very strong repulsion but is always monotonic in disorder.