Phase Transition Kinetics and Critical Phenomena in the Site Diluted Ising Model

Speaker: Kang Liu

When: January 31, 2012 (Tue), 04:30PM to 05:30PM (add to my calendar)
Location: SCI 328

This event is part of the Preliminary Oral Exam.

Examining Committee:  William Klein, Karl Ludwig, Anatoli Polkovnikov, Martin Schmaltz

In this talk, I will present our study on the effect of quenched site dilution on the phase transition kinetics and critical phenomena of the 2D Ising model. First, I will discuss the effect of the dilution on the classical nucleation theory by showing some simulation data for the 2D dilute Ising model with nearest neighbor interactions. Then I will move on to systems with long range interactions, generalize the Harris criterion to mean-field and near mean-field systems and show that the critical exponents of both the critical point and spinodal do not change regardless of the dimensionality. This is supported by measurements of the isothermal susceptibility near the spinodal line from Monte-Carlo simulations. Then I will introduce a coarse-grained field theory for a specific dilution realization using the Hubbard-Stratanovich transformation, and discuss some applications of this field theory. Finally, I will generalize the Coniglio-Klein method by mapping the diluted Ising critical point onto an equivalent site-bond percolation problem.