ENERGY DENSITY PROFILES IN CRITICAL FILMS

Scaling density profiles of critical O(N)-symmetric systems confined t o a film geometry are analyzed by field-theoretic renormalization-grou p techniques in d=4-epsilon spatial dimensions. At bulk criticality we explicitly calculate the energy density profile for five different bo undary conditions and determine their corresponding universal scaling functions. In order to discuss the influence of the boundary condition s at the two surfaces of the film on the global shape of the profiles, a suitable exponentiation scheme is constructed, Using these exponent iated scaling functions as well as results from conformal field theory , the shapes of the energy density profiles in d=2,3, and 4 are compar ed. Finally, we discuss the short-distance behavior of the energy dens ity profiles close to the surfaces of the film as it follows from the knowledge of the full profiles in first order epsilon.