  In this paper we present simulations of a surface-adsorbed polymer subject to
an elongation force. The polymer is modelled by a self-avoiding walk on a
regular lattice. It is confined to a half-space by an adsorbing surface with
attractions for every vertex of the walk visiting the surface, and the last
vertex is pulled perpendicular to the surface by a force. Using the recently
proposed flatPERM algorithm, we calculate the phase diagram for a vast range of
temperatures and forces. The strength of this algorithm is that it computes the
complete density of states from one single simulation. We simulate systems of
sizes up to 256 steps.
