Semiflexible polymer in a strip

We study the thermodynamic properties of a semiflexible polymer confined inside strips of widths L<=9 defined on a square lattice. The polymer is modeled as a self-avoiding walk and a short range interaction between the monomers and the walls is included through an energy e associated to each monomer placed on one of the walls. Also, an additional energy is associated to each elementary bend of the walk. The free energy of the model is obtained exactly through a transfer matrix formalism. The profile of the monomer density and the force on the walls are obtained. We notice that as the bending energy is decreased, the range of values of e for which the density profile is neither convex nor concave increases, and for sufficiently attracting walls (e<0) we find that in general the attractive force is maximum for situations where the bends are favored.