  We explore the properties of weakly bound bosonic states in the strongly
interacting regime. Combining a correlated-Gaussian (CG) basis set expansion
with a complex scaling method, we extract the energies and structural
properties of bosonic cluster states with $N\le6$ for different two-body
potentials. The identification of five- and six-body resonances attached to an
excited Efimov trimer provides strong support to the premise of Efimov
universality in bosonic systems. Our study also reveals a rich structure of
bosonic cluster states. Besides the lowest cluster states which behave as
bosonic droplets, we identify cluster states weakly bound to one or two atoms
forming effective cluster-atom "dimers" and cluster-atom-atom "trimers." The
experimental signatures of these cluster states are discussed.

Quantum Gases