Download or read book Etude vibrationnelle des alliages semi conducteurs II VI et III V written by Ayoub Nassour and published by . This book was released on 2008 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nos travaux sont consacrés à la promotion du modèle de percolation phénoménologique en employant des méthodes indépendantes et libres de tout paramètre. Nous avons utilisé à cet effet des codes ab initio existants (PWscf et SIESTA) et développé une méthode semi-empirique pour étudier les propriétés vibrationnelles des alliages AxB1 xC. Les paramètres techniques du code PWscf ont été testés sur les composés binaires ZnSe, ZnTe et BeSe pour lesquels nous avons confronté nos résultats aux données expérimentales et théoriques disponibles. La validation du modèle de percolation a et e effectué sur l alliage Zn(Se,Te) appartenant à la catégorie des semi-conducteurs 1-liaison ! 2-modes. Nous avons confirmé le caractère général du comportement bimodal prévu par le modèle de percolation en montrant son existence pour chacune des liaisons Zn Se et Zn Te. Les propriétés vibrationnelles et structurales de Zn(Se,Te) ont et e calculées à différentes concentrations avec des cellules optimisées à 64 atomes. Les résultats obtenus sont en bon accord avec l expérience. Nous présentons en détail notre méthode semi-empirique de calcul de spectre de phonons, applicable en principe à tous les alliages sans restriction sur la taille des super-cellules. La mise au point a été réalisé sur les alliages (Zn,Be)Se et (In,Ga)As avec des cellules à64 atomes relaxées d une façon ab initio. L application de notre méthode à(In,Ga)As à 50% simulé par une super-cellule à 8.103 atomes relaxée avec un potentiel harmonique met en évidence que l étude des phonons demande des super-cellules qui reflètent fidèlement le désordre d un alliage
Download or read book Etude Vibrationnelle des Alliages Semi conducteurs written by Ayoub Nassour and published by Editions Universitaires Europeennes. This book was released on 2014-09-05 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nos travaux sont consacres a la promotion du modele de percolation phenomenologique en employant des methodes independantes et libres de tout parametre. Nous avons utilise a cet effet des codes Ab Initio existants (PWscf et SIESTA) et ddeveloppe une methode semi-empirique pour etudier les proprietes vibrationnelles des alliages A(B, C). Les parametres techniques du code PWscf ont ete testes sur les composes binaires ZnSe, ZnTe et BeSe pour lesquels nous avons confronte nos resultats aux donnees experimentales et theoriques disponibles. La validation du modele de percolation a ete effectue sur l'alliage Zn(Se, Te) appartenant a la categorie des semi-conducteurs 1-liaison 2-modes. Nous avons confirme le caractere general du comportement bimodal prevu par le modele de percolation en montrant son existence pour chacune des liaisons Zn Se et Zn Te. Les proprietes vibrationnelles et structurales de Zn(Se, Te) ont ete calculees a differentes concentrations avec des cellules optimisees a 64 atomes. Les resultats obtenus sont en bon accord avec l'experience."
Download or read book CONTRIBUTIONS A L ETUDE THEORIQUE DE LA STRUCTURE ELECTRONIQUE ET DE LA SPECTROSCOPIE DANS LES ALLIAGES SEMICONDUCTEURS written by ABDOUL AZIZ.. M'BAYE and published by . This book was released on 1984 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: ETUDE DES EFFETS DU DESORDRE STATISTIQUE D'ALLIAGE SUR LA STRUCTURE ELECTRONIQUE ET SUR LES SPECTRES DES QUASIPARTICULES SPATIALEMENT ETENDUES (QSE) DANS LES ALLIAGES SEMICONDUCTEURS. DEVELOPPEMENT D'UNE THEORIE D'ALLIAGE CAPABLE DE DECRIRE LES EFFETS DU DESORDRE MESURES PAR UNE QSE. DEVELOPPEMENT D'UN SCHEMA D'INTERPOLATION DU POTENTIEL D'ALLIAGE PRENANT EN COMPTE LES EFFETS INTRINSEQUES (STRUCTURAUX OU DE VOLUME) ET EXTRINSEQUES LIES AU DESORDRE
Download or read book ETUDE DE LA LOCALISATION DES EXCITONS DANS LES ALLIAGES SEMICONDUCTEURS II VI written by DJAMEL.. OUADJAOUT and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: IL S'AGIT D'ABORDER DU POINT DE VUE THEORIQUE ET EXPERIMENTAL LE PROBLEME DE LA LOCALISATION DES EXCITONS DANS LES ALLIAGES SEMICONDUCTEURS II-VI: 1) SUR LE PLAN EXPERIMENTAL DES EXPERIENCES DE PHOTOLUMINESCENCE ET DE PHOTOLUMINESCENCE EXCITEE SELECTIVEMENT ONT ETE MENEES SUR QUELQUES ALLIAGES ZN#XHG#1##XTE RICHES EN ZINC. A BASSE TEMPERATURE, LES SPECTRES DE LUMINESCENCE SONT DOMINES PAR UNE RAIE (L) SITUEE EN DESSOUS DU SEUIL EXCITONIQUE ET INTERPRETEE COMME ETANT DUE A DES EXCITONS LOCALISES DANS UNE QUEUE DE DENSITE D'ETATS (DOS) DERIVEE DES FLUCTUATIONS DE POTENTIEL. PAR AILLEURS, EN DESSOUS DE LA RAIE PRINCIPALE APPARAIT UNE BANDE PLUS LARGE (B), QUI SE DEPLACE VERS LES BASSES ENERGIES QUAND LA TEMPERATURE AUGMENTE. CETTE BANDE PROVIENT D'EXCITONS LIES A DES CENTRES ISOELECTRONIQUES CONSTITUES D'AGREGATS D'ATOMES HG ISOLES DANS LA MATRICE ZNTE; 2) SUR LE PLAN THEORIQUE, NOUS PROPOSONS UN MODELE SIMPLE DE (DOS), OBTENU EN MINIMISANT LA FLUCTUATION D'ENTROPIE ASSOCIEE A LA FLUCTUATION DE COMPOSITION MOYENNEE SUR UN VOLUME V, POUR UNE ENERGIE DE LOCALISATION DONNEE. NOUS INTRODUISONS EGALEMENT UN VOLUME D'INTERACTION CRITIQUE V#C, DEFINI COMME ETANT LE PLUS PETIT VOLUME DANS LEQUEL LA FLUCTUATION PEUT EXISTER. PARTANT DE CETTE FORME DE (DOS), NOUS AVONS MODELISE LA FORME DE LA RAIE DE LUMINESCENCE (L) A BASSE TEMPERATURE. POUR RENDRE COMPTE EGALEMENT DE L'EVOLUTION, EN FONCTION DE LA TEMPERATURE, DE LA RAIE (L) NOUS AVONS ETENDU CE MODELE EN Y INCLUANT LES TERMES RELATIFS A L'ACTIVATION THERMIQUE ENTRE ETATS LOCALISES
Download or read book Modern Surface Organometallic Chemistry written by Jean-Marie Basset and published by John Wiley & Sons. This book was released on 2009-07-10 with total page 725 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering everything from the basics to recent applications, this monograph represents an advanced overview of the field. Edited by internationally acclaimed experts respected throughout the community, the book is clearly divided into sections on fundamental and applied surface organometallic chemistry. Backed by numerous examples from the recent literature, this is a key reference for all chemists.
Download or read book Satellite Situation Report written by Goddard Space Flight Center. Office of Public Affairs and published by . This book was released on 1977 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Offshore Power Systems written by Faye H. Horn and published by . This book was released on 1974 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction To Plasmonics written by Olivier Pluchery and published by World Scientific. This book was released on 2023-08-28 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: What is a plasmon? Is it a particle, like a photon or a wave? Plasmonics stands at the frontier of condensed matter physics, which is the world of electrons, optics and of photons. Plasmonics is one of the most active fields in nanophotonics. This book begins by exploring the concepts behind waves, and the electromagnetic description of light when it interacts with metals; it dedicates every chapter thereafter to all aspects of plasmonics. In particular, the surface plasmon polariton wave is explained in full detail, as well as the localized surface plasmon resonance of metallic nanoparticles. The active research area opened by plasmonics, as well as its applications, are also briefly explained, such as advanced biosensing, subwavelength waveguiding, quantum plasmonics, nanoparticle-based cancer therapies, optical nano-antenna and high-efficiency photovoltaic cells.The book is adapted for graduate students and places a special emphasis on providing complete explanations of the fundamental concepts of plasmonics. Further, each of these concepts is illustrated with examples drawn from the most recent scientific literature. Each chapter ends with a set of exercises that will help the reader revise the concepts and go deeper into the world of plasmonics. More than 70 exercises are included.
Download or read book Space Debris written by Heiner Klinkrad and published by Springer Science & Business Media. This book was released on 2006-09-01 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: The future evolution of the debris environment will be forecast on the basis of traffic models and possible hazard mitigation practices. The text shows how large trackable objects will have re-entry pinpointed and predictions made on related risk assessment for possible ground impact. Models will also be described for meteoroids which are also a prevailing risk.
Download or read book Mass Transport in Oxides written by J. B. Wachtman and published by . This book was released on 1968 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrical Properties of Solids written by T. F. Connolly and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1963 the Research Materials Information Center has been answering inquiries on the availability, preparation, and properties of ultrapure inorganic research specimens. It has been possible to do this with reasonable efficiency by searching an automated coded microfilm collection of the report and open literature and of data sheets and question naires provided by commercial and research producers of pure materials. With the growth of the collection to over 70,000 documents and the increase in the demand for more general background information, it has been necessary to compile bibliographies on an increasing variety of subjects. These have been used as indexes to the microfilmed documents for more efficient searching, and in the past distributed in response to individual requests. However, their size and number no longer permit so casual and uneconomic a method of distribution. The "ORNL Solid State Physics Literature Guides" is a practical alternative. Organization The subject organization of the bibliography is given by the Table of Contents. Each section is preceded by a collection of reviews, bibliographies, and "general" papers (i.e., those dealing with methods or equipment rather than single materials, or with such a wide variety of materials that no subsection was appropriate). Coverage is generally from 1960 to mid-1970. Emphasis is on inorganic materials.
Download or read book Crystal Growth in Gels written by Heinz K. Henisch and published by Courier Corporation. This book was released on 1996-01-01 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: First book ever printed on growing crystals in a gel medium provides thorough descriptions of the procedure, its history and future potential. "Concise and readable."—Science. 42 illus. 1970 edition.
Download or read book Electrochemistry of Semiconductors written by Viktor Alekseevich Miamlin and published by Springer. This book was released on 1967-01-01 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics of Electronic Conduction in Solids written by Frank J. Blatt and published by . This book was released on 1968 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Classification of solids -- Lattice vibrations and lattice specific heat -- Equilibrium properties of a free-electron gas -- Electrons in a periodic lattice -- Transport equation -- Relaxation mechanisms -- Conductivity and related phenomena : metals -- Homogeneous semiconductors -- Rectifying junctions and transistors -- Optical properties of semiconductors -- Properties of semiconductors and metals in strong magnetic fields -- Appendix A. Summary of Elementary Quantum Mechanics -- Appendix B. Units and Conversion factors -- Appendix C. The Periodic Table -- Appendix D. Values of Important Physical Constants and Some Convenient Conversion Factors -- Appendix E. List of Symbols.
Download or read book Ferroelectric Materials and Ferroelectricity written by T. F. Connolly and published by Springer. This book was released on 2013-09-14 with total page 685 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is a joint effort of the Research Materials Information Center (RMIC) of the Solid State Division at Oak Ridge National Laboratory and the Libraries and Information Systems Center at Bell Telephone Laboratories (BTL) Murray Hill, N. J. The Research Materials Information Center has, since 1963, been answering inquiries on the avail ability, preparation, and properties of inorganic solid-state research materials. The preparation of bibliographies has been essential to this function, and the interest in ferroelectrics led to the compila tion of the journal and report literature on that subject. The 1962 book Ferroelectric Crystals, by Jona and Shirane, was taken as a cutoff point, and all papers through mid-1969 received by the Center have been included. The Libraries and Information Systems Center of BTL has, over a period of years, developed a proprie tary package of computer programs called BELDEX, which formats and generates indexes to biblio graphic material. This group therefore undertook to process RMIC's ferroelectric references by BELDEX so that both laboratories could have the benefit of an indexed basic bibliography in this important research area.
Download or read book The Growth of Single Crystals written by R. A. Laudise and published by Prentice Hall. This book was released on 1970 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solid State Surface Science written by Mino Green and published by . This book was released on 1973 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
