Interfacial roughening in field theory

Understand

In the rough phase, the width of interfaces separating different phases of statistical systems increases logarithmically with the system size.

• This phenomenon is commonly described in terms of the capillary wave model, which deals with fluctuating, infinitely thin membranes, requiring ad hoc cut-offs in momentum space.
• We investigate the interface roughening from first principles in the framework of the Landau-Ginzburg model, that is renormalized field theory, in the one-loop approximation.
• The interface profile and width are calculated analytically, resulting in finite expressions with definite coefficients.