A wall having unequal interactions with the two components of a binary mixture is responsible for critical adsorption. We have analyzed with the renormalization-group formalism the scaling laws which govern this phenomenon. Furthermore, we have computed, within the $\epsilon$-expansion formalism, the universal order-parameter profile for a range of possible values of the wall parameters (surface field and decoupling factor).

• Received 13 July 1982

DOI:https://doi.org/10.1103/PhysRevB.27.594