Anharmonic effects on the dynamics of two-dimensional anisotropic melting

Anharmonic effects on the critical dynamics of two-dimensional anisotropic melting arising from the existence of a large regime of smecticlike behavior right above the melting temperature are studied and shown to be irrelevant, despite the strong relevance of such effects for three-dimensional smectics. This irrelevance is due to the finite persistence length of smectic fluctuations in two dimensions. © 1984 The American Physical Society.