Le centre coloré NV, constitué d’un atome d’azote et d’une lacune, est un défaut ponctuel du diamant qui se comporte comme un atome artificiel piégé dans cette matrice. Grâce aux propriétés de son spin électronique, qui peut être lu et manipulé comme un système quantique élémentaire, le centre NV as de nombreuses applications comme qubit pour l’information quantique ou comme sonde de champ magnétique. Cependant, ces applications nécessitent de contrôler les propriétés des centres NV ainsi que leur position dans le cristal. Cette thèse examine des méthodes pour atteindre ces objectifs en combinant des techniques d’implantation d’atomes et de croissance assistée par plasma (CVD) de diamant.Le mémoire est divisé en six chapitres. Le premier chapitre résume les propriétés des centres NV, ce qui permet de définir les objectifs principaux dans la fabrication des centres NV. Le chapitre deux montre qu’il est possible de créer un réseau de centres NV par implantation au moyen d’une colonne d’ions focalisés. Cette technique est adaptée à la création de centres NV dans des nanostructures comme des cristaux photoniques ou des pointes de type AFM. Cependant la faible énergie cinétique des ions, nécessaire pour atteindre une résolution meilleure que 10 nm en diamètre de spot, conduit à une implantation proche de la surface ce qui affecte fortement les propriétés des centres NV. Le troisième chapitre examine comment la recroissance d’une couche de diamant sur des centres NV implantés permet de réduire l’impact négatif de la surface. Les quatrième et cinquième chapitres décrivent des méthodes pour la fabrication des centres NV en contrôlant les paramètres de la croissance CVD. Des couches minces fortement dopées avec les centres NV peuvent être créées, et un contrôle quasi parfait de l’orientation de l’axe du centre NV peut être obtenu. Dans l’objectif d’optimiser les propriétés du temps de cohérence du spin, le sixième chapitre étudie comment le spin électronique du centre NV peut être protégé contre les effets de décohérence induits par les spins non-polarisés dans la matrice du diamant. / The Nitrogen-Vacancy (NV) color center is a defect of diamond which behaves as an artificial atom hosted in a solid-state matrix. Due to its electron spin properties which can be read-out and manipulated as an elementary quantum system, the NV center has found a wide panel of applications as a qubit for quantum information and as a magnetic field sensor. However these applications require to control the properties of the NV centers and their localization. This doctoral thesis investigates methods allowing us to tailor the properties of NV centers by combining techniques for the implantation of nitrogen atoms and the plasma-assisted (CVD) synthesis of diamond.The manuscript is divided into six chapters. The first chapter summarizes the properties of the NV center which will set our objectives for the NV engineering. The second chapter will describe how arrays of NV centers can be created using Focused Ion Beam implantation. The results open a wide range of applications for the targeted creation of NV centers in diamond structures such as photonic crystals and tips. However the low kinetic energy which is required for achieving implantation within a spot of 10-nm diameter leads to shallow defects which properties are strongly affected by the sample surface. The third chapter investigates how the overgrowth of a diamond layer over implanted NV centers can remove the detrimental influence of the surface. The fourth and fifth chapters describe effective methods for NV center fabrication through the control of the CVD growth conditions of the hosting crystal. Thin layers with high NV doping can be grown and almost perfect control of the orientation of the NV axis can be achieved. With the goal to optimize the spin coherence properties, the sixth chapter investigates how the electron spin of the NV center can be protected from decoherence effects induced by magnetic noise due to the unpolarized spins in the diamond lattice.

A realização do trabalho efetuado a seguir, consiste na coleta de informações e a montagem da história da lapidação desde o que o homem primitivo começou a trabalhar os minerais, seu desenvolvimento na Europa até a atual situação da lapidação brasileira. No caráter científico, a identificação e utilização de propriedades físicas e ópticas para determinação do mineral, correlacionando itens como seu melhor aproveitamento na lapidação, como a utilização principalmente do ângulo crítico especifico de cada mineral e sua correta utilização na lapidação de gemas coradas e lapidação de diamantes. Pois o significado da lapidação é transformar o mineral em uma gema aceita pela indústria joalheira, valorizando sua cor, brilho, formato e simetria. No panorama tecnológico a análise de maquinários antigos e tradicionais, juntamente com a inovação de máquinas CNC. Neste trabalho foi presenciado que a fundamentação bibliográfica é restrita para a indústria de lapidação no Brasil. / This work started with a compilation of informations, written and of oral means, to unravel the history of gem cutting from his earliest time to the present situation in Brasil. The scientific part stresses the identification and the use of the physical and optical properties to increase the yield by gemstone cutting. It is shown that the critical angle is the most important property for each branch, the diamond as well the colored gemstone cutting.Gem cutting is the transformation of the rough to a form accepted by the jeweler, showing his best in color, brilliance, form and symmetry. The development of cutting tools is shown from very early times to the present CNC equipment. It could be shown that there exists a quite good data base for an initial description of the gem cutting industry in Brazil.

A realização do trabalho efetuado a seguir, consiste na coleta de informações e a montagem da história da lapidação desde o que o homem primitivo começou a trabalhar os minerais, seu desenvolvimento na Europa até a atual situação da lapidação brasileira. No caráter científico, a identificação e utilização de propriedades físicas e ópticas para determinação do mineral, correlacionando itens como seu melhor aproveitamento na lapidação, como a utilização principalmente do ângulo crítico especifico de cada mineral e sua correta utilização na lapidação de gemas coradas e lapidação de diamantes. Pois o significado da lapidação é transformar o mineral em uma gema aceita pela indústria joalheira, valorizando sua cor, brilho, formato e simetria. No panorama tecnológico a análise de maquinários antigos e tradicionais, juntamente com a inovação de máquinas CNC. Neste trabalho foi presenciado que a fundamentação bibliográfica é restrita para a indústria de lapidação no Brasil. / This work started with a compilation of informations, written and of oral means, to unravel the history of gem cutting from his earliest time to the present situation in Brasil. The scientific part stresses the identification and the use of the physical and optical properties to increase the yield by gemstone cutting. It is shown that the critical angle is the most important property for each branch, the diamond as well the colored gemstone cutting.Gem cutting is the transformation of the rough to a form accepted by the jeweler, showing his best in color, brilliance, form and symmetry. The development of cutting tools is shown from very early times to the present CNC equipment. It could be shown that there exists a quite good data base for an initial description of the gem cutting industry in Brazil.

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-10-10T17:06:04Z No. of bitstreams: 2 Dissertação - José Luiz Vaz de Sousa - 2012.pdf: 12987105 bytes, checksum: e5d6a62427613c271ed88023359617fa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-10T20:28:58Z (GMT) No. of bitstreams: 2 Dissertação - José Luiz Vaz de Sousa - 2012.pdf: 12987105 bytes, checksum: e5d6a62427613c271ed88023359617fa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-10T20:28:58Z (GMT). No. of bitstreams: 2 Dissertação - José Luiz Vaz de Sousa - 2012.pdf: 12987105 bytes, checksum: e5d6a62427613c271ed88023359617fa (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-11-22 / This dissertation comes from the insertion of diamond miners in the process of constitution of socioeconomic Três Ranchos, city located in the extreme southeast of the state of Goiás. Três Ranchos miners risked the fate of most workers, ignored to follow regarding its importance and relationship to the historical process, and the consequences and repercussions that their work resulted in the transformation of the space. Clearly the presence of the miner every day in Três Ranchos, printed marks that remain even after all this time closed the mining of diamonds, which lasted from mid-1930 until 1981. That year he graduated reservoir Hydropower Plant Emborcação, banning workers from places where worked. The mining, extractive, primary, interrupted suddenly function of flooding, has been replaced by others, to cater to tourism arising, those related to the service sector, qualified as the tertiary stage of the economy. This new economic environment (attractive to some, damaging the opinion of others) has as its background the mischaracterization of the territory by the deployment of hydropower, an event that is one of the most striking contemporary designs of capital reproduction. The historical-geographical process, values and habits of the miner, his relationship with the natural and social environment, the socio-cultural contribution, the symbols related to the environment from mining and the diamond itself, the exploitation of labor by “fornecedor” and the “capangueiro”, the consequences for the environment adjacent to mining after the flood, the dispossession of the worker proceeded and how to restructure, etc. are constituent elements of this study. And to understand the plots that engages the diamond (or that are woven in consequence thereof) as well as its geological constitution gives several scientific papers were used. Moreover, as a methodology, considering that memory is an effective appeal to refer to spatiality, and specific documentation on the subject was poor, appealed to the orality of the miners as well as the photographs of the time. Also resorted to fiction and memoir writers and travelers, precious expedients to contribute to clarify what moves these guys. Thus is fulfilled is the central objective proposed, to emphasize the importance of the miner and his work, bringing them to the surface of the story. / Trata esta dissertação da inserção dos garimpeiros de diamantes no processo de constituição socioeconômica de Três Ranchos, Município situado no extremo sudeste do Estado de Goiás. Os garimpeiros de Três Ranchos arriscavam-se à sina da maioria dos trabalhadores, a de seguirem ignorados quanto à sua importância e relação com o processo histórico, e as consequências e repercussões que o seu trabalho ocasionou na transformação do espaço. É evidente a presença do garimpeiro no cotidiano de Três Ranchos, marcas que permanecem impressas mesmo depois de tanto tempo encerrado o garimpo de diamantes, que durou de meados de 1930 até 1981. Nesse ano se formou o reservatório da Usina Hidrelétrica de Emborcação, banindo os trabalhadores dos sítios onde garimpavam. A atividade garimpeira, extrativista, primária, interrompida subitamente em função do alagamento, foi substituída por outras, para atender ao turismo advindo, essas relacionadas ao setor de serviços, qualificado como o estágio terciário da economia. Este novo cenário econômico (atrativo para uns, nocivo na opinião de outros) tem como pano de fundo a descaracterização do território pela implantação de usinas hidroelétricas, evento que é um dos mais flagrantes desenhos contemporâneos da reprodução do capital. O processo histórico-geográfico, os valores e hábitos do garimpeiro, suas relações com o meio natural e social, o aporte sociocultural, as simbologias relacionadas ao ambiente do garimpo e ao próprio diamante, a exploração do trabalho pelo “fornecedor” e pelo “capangueiro”, as consequências para o ambiente adjacente ao garimpo após a inundação, a desterritorialização do trabalhador e como procedeu para se reestruturar, etc, são elementos constitutivos deste estudo. E para entender as tramas em que se envolve o diamante (ou que são tecidas em consequência dele) e também como se dá a sua constituição geológica, vários trabalhos científicos foram utilizados. Ainda, à guisa de metodologia, considerando que a memória é um apelo eficiente para se referir à espacialidade, e que a documentação específica a respeito do assunto era precária, apelou-se à oralidade dos garimpeiros, assim como às fotografias da época. Recorreu-se também à ficção e aos memorialistas e viajantes, preciosos expedientes a contribuir na decifração do que movia estes sujeitos. Dessa forma é que se cumpre o objetivo central proposto, de realçar a importância do garimpeiro e de seu trabalho, trazendo-os para a superfície da história.

This memorandum outlines the role of De Beers and its leading position in the international diamond industry. It is designed to give a brief overview of the “diamond pipeline” that leads from prospecting and mining of diamonds in remote parts of Africa and elsewhere to glamorous jewellers’ shops the world oven It looks particularly at the unique and important role South Africa plays in the diamond pipeline.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2015.

<p>Numerous studies have confirmed a statistically significant negative relationship between natural resource abundance and economic growth. This has been labeled “The Resource Curse”. In this paper we try to explain why Botswana, a country heavily dependent on its diamond industry, has managed to generate sustainable growth. Economists have advanced several explanations for the negative impact of natural resources on long-term growth. This paper focuses on the following important problems: First, a boom in a natural resource can pull resources away from other sectors of the economy, thus harming their international competitiveness, a phenomenon called the Dutch disease. Second, abundance in natural resources may lead to poor institutional quality in many countries. Thanks to conservative fiscal policies and accumulation of foreign reserves the local currency did not appreciate during the boom, and Botswana avoided the most severe symptoms of the Dutch disease. Historical tradition of democratic procedures and sound institutions at the time of diamond discovery has contributed to a high institutional quality in Botswana.</p>

This thesis presents the results of a study on diamonds from the Artemisia kimberlite, Nunavut, Canada. This study integrates the isotopic, chemical and physical characteristics of the diamonds in an attempt to provide insight into the nature of the micro-/macro-diamond genetic relationship, and its possible implication pertaining to the use of size frequency distributions in modern kimberlite exploration programs. Despite geochemical commonalities of the Artemisia micro- and macro-diamonds, distinct signatures are observed, particularly in regards to enriched and depleted carbon isotopic compositions, the abundance of nitrogen and hydrogen impurities and different resorption histories. This implies that, despite an observed lognormal size frequency distribution for Artemisia diamonds, micro- and macro-diamonds do not represent a single population at this locality.

Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 140-152).

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 107-109). Also available on the Internet.