Critical properties of edge-cubic spin model on square lattice (2008)
Surungan, Tasrief, Kawashima, Naoki, Okabe, Yutaka
The edge-cubic spin model on square lattice is studied via Monte Carlo simulation with cluster algorithm. By cooling the system, we found two successive symmetry breakings, i.e., the breakdown of...
Hideaki Okayama, Yutaka Okabe, Takeshi Kamijoh, Nobuyoshi Sakamoto
SUMMARY A large scale optical switch array based on guided-wave technology using banyan network architecture is demonstrated. Banyan network architecture is the simplest NN network connecting a input...
Using the Wang-Landau Monte Carlo method, we study the antiferromagnetic (AF) three-state Potts model with a staggered polarization field on the square lattice. We obtain two phase transitions; one...
Exchange Bias with Interacting Random Anti-ferromagnetic Grains (2006)
A model consisting of random interacting anti-ferromagnetic (AF) grains coupled to a ferromagnetic (FM) layer is developed to study the exchange bias phenomenon. This simple model is able to describe...
Multispin Coding Technique for Nonequilibrium Reweighting (2006)
We present the multispin coding for the nonequlibrium reweighting method of the Monte Carlo simulation, that was developed by the present authors. As an illustration, we treat the driven diffusive...
Otsuka, Hiromi, Okabe, Yutaka, Nomura, Kiyohide
We investigate the triangular-lattice antiferromagnetic Ising model with a spatially anisotropic next-nearest-neighbor ferromagnetic coupling, which was first discussed by Kitatani and Oguchi. By...
Mapping Monte Carlo to Langevin dynamics: A Fokker-Planck approach (2006)
Cheng, X. Z., Jalil, M. B. A., Lee, Hwee Kuan, Okabe, Yutaka
We propose a general method of using the Fokker-Planck equation (FPE) to link the Monte-Carlo (MC) and the Langevin micromagnetic schemes. We derive the drift and disusion FPE terms corresponding to...
Otsuka, Hiromi, Okabe, Yutaka, Okunishi, Kouichi
The field-induced Berezinskii-Kosterlitz-Thouless (BKT) transition in the ground state of the triangular antiferromagnetic Ising model is studied by the level-spectroscopy method. We analyze...
Convergence and Refinement of the Wang-Landau Algorithm (2005)
Lee, Hwee Kuan, Okabe, Yutaka, Landau, D. P.
Recently, Wang and Landau proposed a new random walk algorithm that can be very efficiently applied to many problems. Subsequently, there has been numerous studies on the algorithm itself and many...
Otsuka, Hiromi, Mori, Koutaro, Okabe, Yutaka, Nomura, Kiyohide
We study the square-lattice three-state Potts model with the ferromagnetic next-nearest-neighbor coupling at finite temperature. Using the level-spectroscopy method, we numerically analyze the...
Nonequilibrium Reweighting on the Driven Diffusive Lattice Gas (2005)
The nonequilibrium reweighting technique, which was recently developed by the present authors, is used for the study of the nonequilibrium steady states. The renewed formulation of the nonequlibrium...
Reweighting for Nonequilibrium Markov Processes Using Sequential Importance Sampling Methods (2004)
We present a generic reweighting method for nonequilibrium Markov processes. With nonequilibrium Monte Carlo simulations at a single temperature, one calculates the time evolution of physical...
Solving the Master Equation for Extremely Long Time Scale Calculations (2004)
Lee, Hwee Kuan, Okabe, Yutaka, Cheng, X., Jalil, M. B. A.
The dynamics of magnetic reversal process plays an important role in the design of the magnetic recording devices in the long time scale limit. In addition to long time scale, microscopic effects...
Basin Hopping with Occasional Jumping (2004)
Iwamatsu, Masao, Okabe, Yutaka
Basin-Hopping (BH) or Monte-Carlo Minimization (MCM) is so far the most reliable algorithms in chemical physics to search for the lowest-energy structure of atomic clusters and macromolecular...
We study a square-lattice three-state Potts antiferromagnet with a staggered polarization field at finite temperature. Numerically treating the transfer matrices, we determine two phase boundaries...
Study of the Fully Frustrated Clock Model using the Wang-Landau Algorithm (2004)
Surungan, Tasrief, Okabe, Yutaka, Tomita, Yusuke
Monte Carlo simulations using the newly proposed Wang-Landau algorithm together with the broad histogram relation are performed to study the antiferromagnetic six-state clock model on the triangular...
Transition matrix Monte Carlo method for quantum systems (2003)
Yamaguchi, Chiaki, Kawashima, Naoki, Okabe, Yutaka
We propose an efficient method for Monte Carlo simulation of quantum lattice models. Unlike most other quantum Monte Carlo methods, a single run of the proposed method yields the free energy and the...
Novel Monte Carlo algorithms and their applications (2002)
Okabe, Yutaka, Tomita, Yusuke, Yamaguchi, Chiaki
We describe a generalized scheme for the probability-changing cluster (PCC) algorithm, based on the study of the finite-size scaling property of the correlation ratio, the ratio of the correlation...
We study the finite-size scaling (FSS) property of the correlation ratio, the ratio of the correlation functions with different distances. It is shown that the correlation ratio is a good estimator...
Wang, Jian-Sheng, Okabe, Yutaka
We compare the performance of extremal optimization (EO), flat-histogram and equal-hit algorithms for finding spin-glass ground states. The first-passage-times to a ground state are computed. At...
Broad histogram relation for the bond number and its applications (2002)
Yamaguchi, Chiaki, Kawashima, Naoki, Okabe, Yutaka
We discuss Monte Carlo methods based on the cluster (graph) representation for spin models. We derive a rigorous broad histogram relation (BHR) for the bond number; a counterpart for the energy was...
We present a detailed description of the idea and procedure for the newly proposed Monte Carlo algorithm of tuning the critical point automatically, which is called the probability-changing cluster...
Probability-Changing Cluster Algorithm for Two-Dimensional XY and Clock Models (2002)
We extend the newly proposed probability-changing cluster (PCC) Monte Carlo algorithm to the study of systems with the vector order parameter. Wolff's idea of the embedded cluster formalism is used...
Yamaguchi, Chiaki, Okabe, Yutaka
We apply a newly proposed Monte Carlo method, the Wang-Landau algorithm, to the study of the three-dimensional antiferromagnetic q-state Potts models on a simple cubic lattice. We systematically...
Universal relations in the finite-size correction terms of two-dimensional Ising models (2001)
Okabe, Yutaka, Kawashima, Naoki
Quite recently, Izmailian and Hu [Phys. Rev. Lett. 86, 5160 (2001)] studied the finite-size correction terms for the free energy per spin and the inverse correlation length of the critical...
Crossover and self-averaging in the two-dimensional site-diluted Ising model (2001)
Using the newly proposed probability-changing cluster (PCC) Monte Carlo algorithm, we simulate the two-dimensional (2D) site-diluted Ising model. Since we can tune the critical point of each random...
Finite-size scaling for the Ising model on the Moebius strip and the Klein bottle (2001)
Kaneda, Kazuhisa, Okabe, Yutaka
We study the finite-size scaling properties of the Ising model on the Moebius strip and the Klein bottle. The results are compared with those of the Ising model under different boundary conditions,...
Probability-Changing Cluster Algorithm for Potts Models (2000)
We propose a new effective cluster algorithm of tuning the critical point automatically, which is an extended version of Swendsen-Wang algorithm. We change the probability of connecting spins of the...
Cluster Analysis of the Ising Model and Universal Finite-Size Scaling (2000)
Okabe, Yutaka, Kaneda, Kazuhisa, Tomita, Yusuke, Kikuchi, Macoto, Hu, Chin-Kun
The recent progress in the study of finite-size scaling (FSS) properties of the Ising model is briefly reviewed. We calculate the universal FSS functions for the Binder parameter $g$ and the...
Reducing quasi-ergodicity in a double well potential by Tsallis Monte Carlo simulation (2000)
Iwamatsu, Masao, Okabe, Yutaka
A new Monte Carlo scheme based on the system of Tsallis's generalized statistical mechanics is applied to a simple double well potential to calculate the canonical thermal average of potential...
Application of Monte Carlo Method to Phase Separation Dynamics of Complex Systems (1999)
Okabe, Yutaka, Miyajima, Tsukasa, Ito, Toshiro, Kawakatsu, Toshihiro
We report the application of the Monte Carlo simulation to phase separation dynamics. First, we deal with the phase separation under shear flow. The thermal effect on the phase separation is...
Shape Effects of Finite-Size Scaling Functions for Anisotropic Three-Dimensional Ising Models (1999)
Kaneda, Kazuhisa, Okabe, Yutaka, Kikuchi, Macoto
The finite-size scaling functions for anisotropic three-dimensional Ising models of size $L_1 \times L_1 \times aL_1$ ($a$: anisotropy parameter) are studied by Monte Carlo simulations. We study the...
Cluster Analysis and Finite-Size Scaling for Ising Spin Systems (1999)
Tomita, Yusuke, Okabe, Yutaka, Hu, Chin-Kun
Based on the connection between the Ising model and a correlated percolation model, we calculate the distribution function for the fraction ($c$) of lattice sites in percolating clusters in subgraphs...
Application of exchange Monte Carlo method to ordering dynamics (1999)
We apply the exchange Monte Carlo method to the ordering dynamics of the three-state Potts model with the conserved order parameter. Even for the deeply quenched case to low temperatures, we have...
Kikuchi, Macoto, Okabe, Yutaka
The multi-spin coding of the Monte Carlo simulation of the three-state Potts model on the simple cubic lattice is presented. The ferromagnetic (F) model, the antiferromagnetic (AF) model, and the...
Universal Finite-Size-Scaling Functions (1996)
Okabe, Yutaka, Kikuchi, Macoto
The idea of universal finite-size-scaling functions of the Ising model is tested by Monte Carlo simulations for various lattices. Not only regular lattices such as the square lattice but...
Statistical Dependence Analysis (1996)
Kikuchi, Macoto, Ito, Nobuyasu, Okabe, Yutaka
We review our recent studies on the dynamical correlations in MC simulations from the view point of the statistical dependence. Attentions are paid to the reduction of the statistical degrees of...
Statistical Dependence and Related Topics (1994)
Kikuchi, Macoto, Ito, Nobuyasu, Okabe, Yutaka
On the basis of the dynamical interpretation of Monte Carlo simulations, we discuss the relation of the equilibrium relaxation time, the susceptibility and the statistical error. We introduce a new...
Recycle of random sequences (1993)
Ito, Nobuyasu, Kikuchi, Macoto, Okabe, Yutaka
The correlation between a random sequence and its transformed sequences is studied. In the case of a permutation operation or, in other word, the shuffling operation, it is shown that the correlation...