Lines of Renormalization Group Fixed Points for Fluid and Crystalline Membranes
Unbinding transitions of amphiphilic membranes are studied by a renormalization group (RG) approach. Both for fluid and for crystalline membranes, a whole line of RG fixed points is found. Each line consists of two branches: one branch describes complete unbinding, the other branch represents continuous unbinding transitions. The critical behaviour at the unbinding transition exhibits three scaling regimes A ), B ), and C ). Regime A ) is characterized by essential singularities, and regime B ) by parameter-dependent critical exponents. In regime C ), a discontinuous transition with rather unusual scaling properties is expected by analogy with wetting transitions.