Discontinuous Phase Transitions of Membranes: a Monte Carlo Study

Fluid membranes which experience interaction potentials with a potential barrier are studied by Monte Carlo simulations. For a symmetric double–well potential, the membranes are found to exhibit the same critical behavior as the 2–dimensional Ising model even for zero lateral tension. For an asymmetric adhesion potential with a relatively large potential barrier, the unbound phase is found to nucleate via the formation of membrane `islands' which implies a discontinuous unbinding transition