Long-range correlations in a magnet close to its critical point or in a binary alloy close to a continuous order-disorder transition can substantially enhance the effect of local perturbations. It is demonstrated using a position-space renormalization procedure that quasi-one-dimensional defects which break the symmetry of the order parameter have pronounced effects: They cause long-range critical adsorption profiles and give rise to new universal critical exponents, which are identified and calculated using field-theoretical methods.
Hanke, Andreas, "Critical Adsorption on Defects in Ising Magnets and Binary Alloys" (2000). Physics and Astronomy Faculty Publications and Presentations. 377.
Physical Review Letters