Phase behaviour of colloidal assemblies on 2D corrugated substrates

Samir El Shawish 1, Emmanuel Trizac 2, Jure Dobnikar 1

Journal of Physics: Condensed Matter 24 (2012) 284118

We investigate - with Monte Carlo computer simulations - the phase behaviour of dimeric colloidal molecules on periodic substrates with square symmetry. The molecules are formed in a two-dimensional suspension of like charged colloids subject to periodic external confinement, which can be experimentally realized by optical methods. We study the evolution of positional and orientational order by varying the temperature across the melting transition. We propose and evaluate appropriate order parameters as well as the specific heat capacity and show that the decay of positional correlations belongs to a class of crossover transitions while the orientational melting is a second-order phase transition.

  • 1. Jozef Stefan Institute,
    Jozef Stefan Institute
  • 2. Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS),
    CNRS : UMR8626 – Université Paris XI - Paris Sud