  An improved variational ansatz is proposed to capture the most striking
properties of the ground state of a slightly biased attractive two-site
Bose-Hubbard Hamiltonian. Our ansatz, albeit its simplicity, is found to
capture well the exact properties of the ground state for a wide variety of
model parameters, in particular the fragmentation occurring before the
formation of cat-like states and also the formation of strongly correlated
cat-like states.
