Domain growth in Ising systems with quenched disorder.

نویسندگان

  • Raja Paul
  • Sanjay Puri
  • Heiko Rieger
چکیده

We present results from extensive Monte Carlo (MC) simulations of domain growth in ferromagnets and binary mixtures with quenched disorder. These are modeled by the random-bond Ising model and the dilute Ising model with either nonconserved (Glauber) spin-flip kinetics or conserved (Kawasaki) spin-exchange kinetics. In all cases, our MC results are consistent with power-law growth with an exponent theta(T, epsilon) which depends on the quench temperature T and the disorder amplitude epsilon. Such exponents arise naturally when the coarsening domains are trapped by energy barriers that grow logarithmically with the domain size. Our MC results show excellent agreement with the predicted dependence of theta(T, epsilon).

برای دانلود 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

Unusual Domain Growth Behavior in the Compressible Ising Model

Large scale Monte Carlo simulations have been used to study long-time domain growth behavior in a compressible, two-dimensional Ising model undergoing phase separation. The system is quenched below the transition temperature from a random spin state, and we investigated the late-time domain size growth law, R(t) = A+Btn. For “lattice mismatched” systems, we found n = 0.224± 0.004 which deviates...

متن کامل

Magnetization Switching in Single-Domain Ferromagnets

A model for single-domain uniaxial ferromagnetic particles with high anisotropy, the Ising model, is studied. Recent experimental observations have been made of the probability that the magnetization has not switched, PNOT. Here an approach is described in which it is emphasized that a ferromagnetic particle in an unfavorable field is in fact a metastable system, and the switching is accomplish...

متن کامل

Zero Temperature Dynamics of the Weakly-disordered Ising Model

The Glauber dynamics of the pure and weakly-disordered random-bond 2d Ising model is studied at zero-temperature. The coarsening length scale, L(t), is extracted from the equal time correlation function. In the pure case, the persistence probability decreases algebraically with L(t). In the disordered case, three distinct regimes are identified: a short time regime where the behaviour is pure-l...

متن کامل

Temporally disordered Ising models

– A study of the influence of different types of disorder on systems in the Ising universality class by employing both a dynamical field theory approach and extensive Monte Carlo simulations is presented. We reproduce some well-known results for the case of quenched disorder (random temperature and random field), and analyze the effect of four different types of time-dependent disorder scarcely...

متن کامل

Domain Growth in Random Magnets

– We study the kinetics of domain growth in ferromagnets with random exchange interactions. We present detailed Monte Carlo results for the nonconserved random-bond Ising model, which are consistent with power-law growth with a variable exponent. These results are interpreted in the context of disorder barriers with a logarithmic dependence on the domain size. Further, we clarify the implicatio...

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

برای دانلود 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

عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 71 6 Pt 1  شماره 

صفحات  -

تاریخ انتشار 2005