Download or read book ETUDE PAR SIMULATION MONTE CARLO ET DIFFRACTION DE RAYONS X DE LA CINETIQUE DE MISE EN ORDRE DANS LES ALLIAGES written by Xavier Flament and published by . This book was released on 2000 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOUS ETUDIONS PAR SIMULATION MONTE-CARLO ET PAR DIFFRACTION DE RAYONS X LA CINETIQUE DE MISE EN ORDRE DANS DEUX SYSTEMES TRES INTERESSANTS : PD 3V (SYSTEME DEGENERE) ET CU 3PD (SYSTEME INCOMMENSURABLE AVEC INTERACTIONS A LONGUE PORTEE). DANS LE CAS DE PD 3V, UNE ETUDE EN CVM A MONTRE QUE LA DEGENERESCENCE ENTRE LA PHASE L1 2, CONSTRUITE SUR DES ONDES DE CONCENTRATION DE TYPE (100), ET LA PHASE STABLE DO 2 2, CONSTRUITE SUR DES ONDES DE TYPE (100) ET (1/2 1 0), SE MANIFESTE PAR UNE INVERSION DES TEMPERATURES D'INSTABILITE (SPINODALES). DANS CE CONTEXTE, NOUS PREDISONS, OUTRE LES REGIMES DE GERMINATION-CROISSANCE ET DE MISE EN ORDRE SPINODALE, L'EXISTENCE D'UN MECANISME DE MISE EN ORDRE INTERMEDIAIRE. CELUI-CI EST MIS EN EVIDENCE NUMERIQUEMENT ET EXPERIMENTALEMENT. IL SE CARACTERISE PAR L'APPARITION UNIFORME D'UN ORDRE A LONGUE DISTANCE (OLD) DE TYPE (100) AVEC UN ORDRE LOCAL (OCD) DE TYPE (1/2 1 0). BIEN ENTENDU, CET OCD SE TRANSFORME ULTERIEUREMENT EN OLD POUR FORMER LA STRUCTURE D'EQUILIBRE DO 2 2. L'ETUDE DE CU 3PD, POUR POUVOIR ETRE ABORDEE EN MONTE-CARLO, A NECESSITE LA DETERMINATION DE POTENTIELS D'INTERACTIONS A LONGUE PORTEE A PARTIR D'EXPERIENCES DE DIFFUSION DIFFUSE, VIA DES METHODES DE PHYSIQUE STATISTIQUE INVERSE. CETTE PROCEDURE A ICI PROUVE SA SOLIDITE PUISQUE LES INTERACTIONS, OBTENUES JUSQU'AU 5 E M E CUBE CFC, NOUS ONT PERMIS DE REPRODUIRE LE DIAGRAMME DE PHASE COMPLEXE DE CU 3PD (STRUCTURES A LONGUE PERIODE 1D ET 2D). LES APPROCHES NUMERIQUE ET EXPERIMENTALE DE LA MISE EN ORDRE VERS CES DEUX TYPES DE STRUCTURES DONNENT DES RESULTATS REMARQUABLEMENT SIMILAIRES. NOTAMMENT, LA CINETIQUE VERS LA PHASE 1D MONTRE UNE CROISSANCE DU SATELLITE DE PREMIER ORDRE PLUS RAPIDE QUE CELLE DE LA SURSTRUCTURE. CE RESULTAT
Download or read book tude de la pr cipitation en dynamique d amas dans les alliages d aluminium et dans les aciers written by Ludovic Laé and published by . This book was released on 2004 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: La prédiction des cinétiques de précipitation dans les alliages métalliques est un enjeu industriel majeur. Cette étude, dont le sujet principal est la modélisation de la précipitation homogéne en dynamique d'amas, traduit la volonté d'aboutir à une meilleure compréhension des phénoménes mis en jeu. Dans un premier temps, un domaine d'accord a pu être trouvé entre cette technique et les outils basés sur la théorie classique de la germination. L'influence de la précision du calcul de l'énergie libre des amas sur les cinétiques de germination a ensuite été étudiée lors de comparaisons entre la dynamique d'amas et Monte Carlo Cinétique, sur les systèmes binaires fer-cuivre, aluminium-zirconium et aluminium-scandium. L'accord obtenu a permis le développement d'un modèle de dynamique d'amas prenant en compte l'absence partielle de stoechiométrie des précipités L 12 AI3ZrXSc1-X dans les alliages ternaires AIZrSc dont les résultats de simulation ont été confrontés à des simulations Monte Carlo Cinétique. Ce système a également fait l'objet d'une caractérisation expérimentale en diffusion centrale des rayons X et en microscopie électronique en transmission. Elle a permis de suivre l'évolution, durant les premiers stades de la précipitation, de la fraction précipitée, du rayon moyen des particules ainsi sur les alliages AIZrSc que de leur composition. Les études tant théoriques qu'expérimentales ont mises en évidence la forte compétition entre les chemins thermodynamiques préférentiels et cinétiques ainsi que l'effet de la ségrégation du zirconium à la surface des précipités sur les cinétiques de coalescence.
Download or read book Quantum Monte Carlo Methods in Physics and Chemistry written by M.P. Nightingale and published by Springer Science & Business Media. This book was released on 1998-12-31 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years there has been a considerable growth in interest in Monte Carlo methods, and quantum Monte Carlo methods in particlular. Clearly, the ever-increasing computational power available to researchers, has stimulated the development of improved algorithms, and almost all fields in computational physics and chemistry are affected by their applications. Here we just mention some fields that are covered in the lecture notes contained in this volume, viz. electronic structure studies of atoms, molecules and solids, nuclear structure, and low- or zero-temperature studies of strongly-correlated quantum systems, both of the continuum and lattice variety, and cooperative phenomena in classical systems. Although each area of application may have its own peculiarities, requiring specialized solutions, all share the same basic methodology. It was with the intention of bringing together researchers and students from these various areas that the NATO Advanced Study Institute on Quantum Monte Carlo Methods in Physics and Chemistry was held at Cornell University from 12 to 24 July, 1998. This book contains material presented at the Institute in a series of mini courses in quantum Monte Carlo methods. The program consisted of lectures predominantly of a pedagogical nature, and of more specialized seminars. The levels varied from introductory to advanced, and from basic methods to applications; the program was intended for an audience working towards the Ph.D. level and above. Despite the essentially pedagogic nature of the Institute, several of the lectures and seminars contained in this volume present recent developments not previously published.
Download or read book Monte Carlo Methods in Chemical Physics written by David M. Ferguson and published by John Wiley & Sons. This book was released on 2009-09-09 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Monte Carlo Methods in Chemical Physics: An Introduction to the Monte Carlo Method for Particle Simulations J. Ilja Siepmann Random Number Generators for Parallel Applications Ashok Srinivasan, David M. Ceperley and Michael Mascagni Between Classical and Quantum Monte Carlo Methods: "Variational" QMC Dario Bressanini and Peter J. Reynolds Monte Carlo Eigenvalue Methods in Quantum Mechanics and Statistical Mechanics M. P. Nightingale and C.J. Umrigar Adaptive Path-Integral Monte Carlo Methods for Accurate Computation of Molecular Thermodynamic Properties Robert Q. Topper Monte Carlo Sampling for Classical Trajectory Simulations Gilles H. Peslherbe Haobin Wang and William L. Hase Monte Carlo Approaches to the Protein Folding Problem Jeffrey Skolnick and Andrzej Kolinski Entropy Sampling Monte Carlo for Polypeptides and Proteins Harold A. Scheraga and Minh-Hong Hao Macrostate Dissection of Thermodynamic Monte Carlo Integrals Bruce W. Church, Alex Ulitsky, and David Shalloway Simulated Annealing-Optimal Histogram Methods David M. Ferguson and David G. Garrett Monte Carlo Methods for Polymeric Systems Juan J. de Pablo and Fernando A. Escobedo Thermodynamic-Scaling Methods in Monte Carlo and Their Application to Phase Equilibria John Valleau Semigrand Canonical Monte Carlo Simulation: Integration Along Coexistence Lines David A. Kofke Monte Carlo Methods for Simulating Phase Equilibria of Complex Fluids J. Ilja Siepmann Reactive Canonical Monte Carlo J. Karl Johnson New Monte Carlo Algorithms for Classical Spin Systems G. T. Barkema and M.E.J. Newman
Download or read book Quantum Monte Carlo Methods in Condensed Matter Physics written by Masuo Suzuki and published by World Scientific. This book was released on 1993 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews recent developments of quantum Monte Carlo methods and some remarkable applications to interacting quantum spin systems and strongly correlated electron systems. It contains twenty-two papers by thirty authors. Some of the features are as follows. The first paper gives the foundations of the standard quantum Monte Carlo method, including some recent results on higher-order decompositions of exponential operators and ordered exponentials. The second paper presents a general review of quantum Monte Carlo methods used in the present book. One of the most challenging problems in the field of quantum Monte Carlo techniques, the negative-sign problem, is also discussed and new methods proposed to partially overcome it. In addition, low-dimensional quantum spin systems are studied. Some interesting applications of quantum Monte Carlo methods to fermion systems are also presented to investigate the role of strong correlations and fluctuations of electrons and to clarify the mechanism of high-c superconductivity. Not only thermal properties but also quantum-mechanical ground-state properties have been studied by the projection technique using auxiliary fields. Further, the Haldane gap is confirmed by numerical calculations. Active researchers in the forefront of condensed matter physics as well as young graduate students who want to start learning the quantum Monte Carlo methods will find this book useful.
Download or read book Recent Advances in Quantum Monte Carlo Methods written by W. A. Lester and published by World Scientific. This book was released on 1997 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: The quantum Monte Carlo (QMC) method is gaining interest as a complement to basis set ab initio methods in cases where high accuracy computation of atomic and molecular properties is desired. This volume focuses on recent advances in this area. QMC as used here refers to methods that directly solve the Schrdinger equation, for example, diffusion and Green's function Monte Carlo, as well as variational Monte Carlo. The latter is an approach to computing atomic and molecular properties by the Monte Carlo method that has fundamental similarities to basis set methods with the exception that the limitation to one-particle basis functions to facilitate integral evaluation is avoided. This feature makes possible the consideration of many-body wave functions containing explicitly interparticle distances ? a capability common to all variants of QMC.
Download or read book The Monte Carlo Method in Condensed Matter Physics written by Kurt Binder and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Monte Carlo method is now widely used and commonly accepted as an important and useful tool in solid state physics and related fields. It is broadly recognized that the technique of "computer simulation" is complementary to both analytical theory and experiment, and can significantly contribute to ad vancing the understanding of various scientific problems. Widespread applications of the Monte Carlo method to various fields of the statistical mechanics of condensed matter physics have already been reviewed in two previously published books, namely Monte Carlo Methods in Statistical Physics (Topics Curro Phys. , Vol. 7, 1st edn. 1979, 2ndedn. 1986) and Applications of the Monte Carlo Method in Statistical Physics (Topics Curro Phys. , Vol. 36, 1st edn. 1984, 2nd edn. 1987). Meanwhile the field has continued its rapid growth and expansion, and applications to new fields have appeared that were not treated at all in the above two books (e. g. studies of irreversible growth phenomena, cellular automata, interfaces, and quantum problems on lattices). Also, new methodic aspects have emerged, such as aspects of efficient use of vector com puters or parallel computers, more efficient analysis of simulated systems con figurations, and methods to reduce critical slowing down at i>hase transitions. Taken together with the extensive activity in certain traditional areas of research (simulation of classical and quantum fluids, of macromolecular materials, of spin glasses and quadrupolar glasses, etc.
Download or read book Monte Carlo Simulation in Statistical Physics written by Kurt Binder and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: When leaming very formal material one comes to a stage where one thinks one has understood the material. Confronted with a "reallife" problem, the passivity of this understanding sometimes becomes painfully elear. To be able to solve the problem, ideas, methods, etc. need to be ready at hand. They must be mastered (become active knowledge) in order to employ them successfully. Starting from this idea, the leitmotif, or aim, of this book has been to elose this gap as much as possible. How can this be done? The material presented here was born out of a series of lectures at the Summer School held at Figueira da Foz (Portugal) in 1987. The series of lectures was split into two concurrent parts. In one part the "formal material" was presented. Since the background of those attending varied widely, the presentation of the formal material was kept as pedagogic as possible. In the formal part the general ideas behind the Monte Carlo method were developed. The Monte Carlo method has now found widespread appli cation in many branches of science such as physics, chemistry, and biology. Because of this, the scope of the lectures had to be narrowed down. We could not give a complete account and restricted the treatment to the ap plication of the Monte Carlo method to the physics of phase transitions. Here particular emphasis is placed on finite-size effects.
Download or read book Monte Carlo Methods in Quantum Problems written by M.H. Kalos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monte Carlo methods have been a tool of theoretical and computational scientists for many years. In particular, the invention and percolation of the algorithm of Metropolis, Rosenbluth, Rosenbluth, Teller, and Teller sparked a rapid growth of applications to classical statistical mechanics. Although proposals for treatment of quantum systems had been made even earlier, only a few serious calculations had heen carried out. Ruch calculations are generally more consuming of computer resources than for classical systems and no universal algorithm had--or indeed has yet-- emerged. However, with advances in techniques and in sheer computing power, Monte Carlo methods have been used with considerable success in treating quantum fluids and crystals, simple models of nuclear matter, and few-body nuclei. Research at several institutions suggest that they may offer a new approach to quantum chemistry, one that is independent of basis ann yet capable of chemical accuracy. That. Monte Carlo methods can attain the very great precision needed is itself a remarkable achievement. More recently, new interest in such methods has arisen in two new a~as. Particle theorists, in particular K. Wilson, have drawn attention to the rich analogy between quantum field theoty and statistical mechanics and to the merits of Monte Carlo calculations for lattice gauge theories. This has become a rapidly growing sub-field. A related development is associated with lattice problems in quantum physics, particularly with models of solid state systems. The~ is much ferment in the calculation of various one-dimensional problems such as the'Hubbard model.
Download or read book Recent Advances in Quantum Monte Carlo Methods written by W. A. Lester and published by World Scientific. This book was released on 2002 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: This invaluable book consists of 16 chapters written by some of the most notable researchers in the field of quantum Monte Carlo, highlighting the advances made since Lester Jr.''s 1997 monograph with the same title. It may be regarded as the proceedings of the Symposium on Advances in Quantum Monte Carlo Methods held during the Pacifichem meeting in December 2000, but the contributions go beyond what was presented there.
Download or read book Quantum Monte Carlo Approaches for Correlated Systems written by Federico Becca and published by Cambridge University Press. This book was released on 2017-11-30 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past several decades, computational approaches to studying strongly-interacting systems have become increasingly varied and sophisticated. This book provides a comprehensive introduction to state-of-the-art quantum Monte Carlo techniques relevant for applications in correlated systems. Providing a clear overview of variational wave functions, and featuring a detailed presentation of stochastic samplings including Markov chains and Langevin dynamics, which are developed into a discussion of Monte Carlo methods. The variational technique is described, from foundations to a detailed description of its algorithms. Further topics discussed include optimisation techniques, real-time dynamics and projection methods, including Green's function, reptation and auxiliary-field Monte Carlo, from basic definitions to advanced algorithms for efficient codes, and the book concludes with recent developments on the continuum space. Quantum Monte Carlo Approaches for Correlated Systems provides an extensive reference for students and researchers working in condensed matter theory or those interested in advanced numerical methods for electronic simulation.
Download or read book The Monte Carlo Methods in Atmospheric Optics written by G.I. Marchuk and published by Springer. This book was released on 2013-04-17 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph is devoted to urgent questions of the theory and applications of the Monte Carlo method for solving problems of atmospheric optics and hydrooptics. The importance of these problems has grown because of the increas ing need to interpret optical observations, and to estimate radiative balance precisely for weather forecasting. Inhomogeneity and sphericity of the atmos phere, absorption in atmospheric layers, multiple scattering and polarization of light, all create difficulties in solving these problems by traditional methods of computational mathematics. Particular difficulty arises when one must solve nonstationary problems of the theory of transfer of narrow beams that are connected with the estimation of spatial location and time characteristics of the radiation field. The most universal method for solving those problems is the Monte Carlo method, which is a numerical simulation of the radiative-transfer process. This process can be regarded as a Markov chain of photon collisions in a medium, which result in scattering or absorption. The Monte Carlo tech nique consists in computational simulation of that chain and in constructing statistical estimates of the desired functionals. The authors of this book have contributed to the development of mathemati cal methods of simulation and to the interpretation of optical observations. A series of general method using Monte Carlo techniques has been developed. The present book includes theories and algorithms of simulation. Numerical results corroborate the possibilities and give an impressive prospect of the applications of Monte Carlo methods.
Download or read book Mesures et simulation par Monte Carlo d ordre local et de d placements lastiques dans l alliage Al Zn written by Joël Desplat and published by . This book was released on 1994 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: La présence d'une énergie élastique, modifie les caractères des transitions ordre/désordre ou démixtion dans les alliages. Cette influence a généralement été étudiée d'un point de vue thermodynamique par des approches macroscopiques. D'autre part, la diffusion diffuse de neutrons permet d'accéder simultanément à l'ordre à courte distance et aux déplacements atomiques dans les cristaux. Ce travail vise à discuter l'influence des effets de taille sur les diagrammes de phases (dissymétrie et fluctuations). Nous avons utilisé un modèle microscopique, basé sur l'Hamiltonien d'Ising ferromagnétique limité aux premiers voisins, qui permet de prendre en compte les effets élastiques. A partir d'une approximation de champ moyen, (théorie de Landau), nous avons relié par un calcul analytique ces effets au déplacement d'une lacune de démixtion. En utilisant un algorithme de Métropolis, nous avons ensuite construit des programmes de simulation de Monte-Carlo. Ceux-ci ont permis de calculer à la fois le diagramme de phases et fa diffusion diffuse de systèmes à démixtion cfc, et de confirmer les tendances mises en évidence par le champ moyen. Cette technique a été appliquée au cas du système Al-Zn. Des mesures de diffusion diffuse nous ont permis de vérifier la présence d'effets de taille, et d'obtenir des potentiels d'interaction de paires à partir de l'ordre local. Par simulation de notre modèle, ces derniers nous ont permis de reproduire qualitativement le diagramme de phases et la section efficace de diffusion diffuse expérimentaux. Le comportement critique, expérimental et simulé, de ce système est voisin de celui de l'Hamiltonien d'Ising non perturbé. Ces résultats sont en accord avec ceux d'études plus anciennes.
Download or read book Monte Carlo Calculations of Gamma Ray Penetration written by Herbert Steinberg and published by . This book was released on 1960 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monte Carlo Simulation in the Radiological Sci written by Richard L. Morin and published by Springer. This book was released on 1988-07-31 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Monte Carlo for Radiation Physics Particle Transport Simulation and Applications written by Andreas Kling and published by Springer. This book was released on 2001-10-02 with total page 1224 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the state of the art of Monte Carlo methods in radiation physics and particle transport simulation and applications. Special attention is paid to algorithm development for modeling, and the analysis of experiments and measurements in a variety of fields.
Download or read book An Introduction to Quantum Monte Carlo Methods written by Tao Pang and published by Morgan & Claypool Publishers. This book was released on 2016-12-07 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monte Carlo methods have been very prominent in computer simulation of various systems in physics, chemistry, biology, and materials science. This book focuses on the discussion and path-integral quantum Monte Carlo methods in many-body physics and provides a concise but complete introduction to the Metropolis algorithm and its applications in these two techniques. To explore the schemes in clarity, several quantum many-body systems are analysed and studied in detail. The book includes exercises to help digest the materials covered. It can be used as a tutorial to learn the discussion and path-integral Monte Carlo or a recipe for developing new research in the reader's own area. Two complete Java programs, one for the discussion Monte Carlo of 4^He clusters on a graphite surface and the other for the path-integral Monte Carlo of cold atoms in a potential trap, are ready for download and adoption.
