N-color Ashkin-Teller model

نویسندگان

  • Gary S. Grest
  • Michael Widom
چکیده

shows nonuniversal critical behavior in two dimensions in the neighborhood of K4 =0. To see if this behavior persists for N & 2 we perform a first-order-perturbation expansion around the decoupling point in two dimensions. As an aid in interpreting the results of this perturbation expansion we have determined the phase diagram of the system through mean-field theory and Monte Carlo studies in 10th two and three dimensions for N = 3. The results show that N = 2 is special because the coupling between Ising models is marginal over a range of values of K4. %'e discuss the effect of the coupling K4 for N W 2.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

6 M ay 2 00 6 Cluster Simulation of the O ( N ) loop model on the Honeycomb lattice

We study the O(N) loop model on the Honeycomb lattice with real value N ≥ 1 by means of a cluster algorithm. The formulation of the algorithm is based on the equivalence of the O(N) loop model and the low-temperature graphical representation of a N -color Ashkin-Teller model on the triangular lattice. The latter model with integer N can be simulated by means of an embedding Swendsen-Wang-type c...

متن کامل

Carlo study of very weak first - order transitions in the three - dimensional Ashkin - Teller model

We propose numerical simulations of the Ashkin-Teller model as a foil for theoretical techniques for studying very weakly first-order phase transitions in three dimensions. The Ashkin-Teller model is a simple two-spin model whose parameters can be adjusted so that it has an arbitrarily weakly first-order phase transition. In this limit, there are quantities characterizing the firstorder transit...

متن کامل

Lebowitz Inequalities for Ashkin–teller Systems

We consider the Ashkin–Teller model with negative four-spin coupling but still in the region where the ground state is ferromagnetic. We establish the standard Lebowitz inequality as well as the extension that is necessary to prove a divergent susceptibility.

متن کامل

Bond disorder induced criticality of the three-color Ashkin-Teller model.

An intriguing result of statistical mechanics is that a first-order phase transition can be rounded by disorder coupled to energylike variables. In fact, even more intriguing is that the rounding may manifest itself as a critical point, quantum or classical. In general, it is not known, however, what universality classes, if any, such criticalities belong to. In order to shed light on this ques...

متن کامل

Monte Carlo study of very weak first - order transitions in the three - dimensional Ashkin - Teller model

We propose numerical simulations of the Ashkin-Teller model as a foil for theoretical techniques for studying very weakly first-order phase transitions in three dimensions. The Ashkin-Teller model is a simple two-spin model whose parameters can be adjusted so that it has an arbitrarily weakly first-order phase transition. In this limit, there are quantities characterizing the firstorder transit...

متن کامل

A Cluster Method for the Ashkin–Teller Model

A cluster Monte Carlo algorithm for the Ashkin-Teller (AT) model is constructed according to the guidelines of a general scheme for such algorithms. Its dynamical behaviour is tested for the square lattice AT model. We perform simulations on the line of critical points along which the exponents vary continuously, and find that critical slowing down is significantly reduced. We find continuous v...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2011