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Remarkable improvements in vertical-cavity surface-emitting lasers (VCSELs) have been made by the introduction of mode- and current-confining oxide optical aperture now used commercially. However, the oxide aperture blocks heat flow inside the device, causing a larger thermal resistance, and the internal strain caused by the oxide can degrade device reliability, also the diffusion process used for the oxide formation can limit device uniformity and scalability. Oxide-free lithographic VCSELs are introduced to overcome these device limitations, with both the mode and current confined within the lithographically defined intracavity mesa, scaling and mass production of small size device could be possible. The 3 μm diameter lithographic VCSEL shows a threshold current of 260 μA, differential quantum efficiency of 60% and maximum output power density of 65 kW/cm2 , and shows single-mode singlepolarization operation with side-mode-suppression-ratio over 25 dB at output power up to 1 mW. The device also shows reliable operation during 1000 hours stress test with high injection current density of 142 kA/cm2 . The lithographic VCSELs have much lower thermal resistance than oxide-confined VCSELs due to elimination of the oxide aperture. The improved thermal property allows the device to have wide operating temperature range of up to 190 °C heat sink temperature, high output power density especially in small device, high rollover current density and high rollover cavity temperature. Research is still underway to reduce the operating voltage of lithographic VCSELs for high wall plug efficiency, and the voltage of 6 µm device at injection current density of 10 kA/cm2 is reduces to 1.83 V with optimized mesa and DBR mirror iv structure. The lithographic VCSELS are promising to become the next generation VCSEL technology.

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This dissertation conducts the first systematic study of illustrated Shahnama manuscripts from Qajar Iran (1789-1925). The Shahnama is a Persian epic, composed by the poet Firdawsi (940-1020 or 1025) in the eleventh century. Over time, the Shahnama became the most frequently illustrated Persian text and manuscript copies of the epic continued to be made in nineteenth-century Iran. However, rather than studying the continued production of illustrated manuscripts, scholarship on Qajar Iran has thus far privileged monumental oil paintings, photography, and lithography. I propose that in nineteenth-century Iran, illustrated Shahnama manuscripts were a potent tool for the ruling class and other ambitious individuals to express and build their identity, lineage, and power, despite the availability of other—and more public—ways to communicate the same message. A vibrant network of manuscript painters, who also worked in other media, produced these illustrated Shahnama copies in dialogue with novel forms of cultural production. Specifically, I argue that illustrated manuscripts and lithographed editions of the epic were created by overlapping circles of artists and they demonstrate how Iran and India were part of a shared cultural zone. By explaining how these two media existed in a dialogical relationship, affecting one another, this project challenges the narrative of teleological progression from one medium to the next. I center my discussion around eleven illustrated Shahnama examples and examine the manuscripts both as individual units and as interrelated parts of a group. I focus on their contexts of production, including patronage, intended audience, and artist workshop and pedagogical relationships. In Chapter 1, I study two early-nineteenth-century illustrated manuscripts (Or. 4906 in the British Library and Lewis O.58 in the Free Library) and explain how each underscored the Qajars’ royal identity and dynastic legitimacy during a period of intense competition for the throne and territorial instability. Chapter 2 explains that military leaders and elite administrators were key drivers of illustrated Shahnama manuscript production. I anchor my discussion around MS 535 in the Matenadaran Library in Armenia to outline how non-royally-commissioned manuscripts mirror the patrons’ political aspirations. Chapter 2 also traces the shared motifs that link one manuscript to another and shows that Shiraz was a major production center for illustrated Shahnama manuscripts. The visual repetitions and adaptations I identify in these manuscripts show that the period’s landscape of artistic production was a tightly woven network of artists’ pedagogical and working relationships. Chapters 3 and 4 focus on the Shahnama books from the latter half of the nineteenth century, including lithographed editions printed in Bombay and illustrated manuscripts made in Iran. Images in these books display the flexibility of the artists as they began to work on both manuscripts and lithographed books; developed unique compositions rooted in the cultural and economic ties connecting Shiraz and Bombay; and expressed artistic agency and authorship as they produced for a speculative market. The four chapters together offer a fresh perspective on the Qajar dynasty’s imperial and ideological usages of the epic, the period’s active non-royal patronage and vibrant workshop practices, and Qajar society’s cultural connections to India, all of which distinctively contributed to building a visual language unique to nineteenth-century Iran.

Le travail de thèse présenté dans ce manuscrit concerne d’une part l’étude théorique des résonances plasmon de nanoparticules métalliques, et d’autre part une étude expérimentale d’inscription de nanostructures métalliques basée sur l’utilisation d’un Microscope à Force Atomique. La partie théorique présente une nouvelle approche phénoménologique permettant l’analyse des modes de résonance propres de particules uniques ainsi que de leur couplage dans des structures simples. Des algorithmes numériques ont été développés afin d’extraire les différents paramètres phénoménologiques à partir du calcul rigoureux du champ diffusé par les particules. Cette méthodologie a été appliquée à divers cas allant de la particule unique à des réseaux à deux dimensions de particules. La partie expérimentale développe une méthode d’inscription de nanostructures métalliques basée sur une réduction électrolytique d’ions métalliques présents dans une couche de silice méso-poreuse, en appliquant une différence de potentiel entre une pointe AFM conductrice et le substrat conducteur supportant la couche. Des structures sont formées de part et d’autre de la couche de silice, avec la possibilité de commuter leur position par simple inversion du potentiel appliqué. De plus, il apparait que cette commutation est accompagnée de modifications dans la conductivité locale de la couche de silice. Une conséquence du processus d’inscription est la formation de filaments métalliques à l’extrémité des pointes AFM. En particulier, des filaments d’or sont obtenus avec des dimensions allant de quelques dizaines à quelques centaines de nanomètres de long pour une épaisseur de quelques nanomètres / The thesis presented in this manuscript concerns firstly the theoretical study of plasmon resonances of metal nanoparticles, and also an experimental study metallic nanostructures inscription based on the use of an Atomic Force Microscope. The theoretical part presents a new phenomenological approach for analyzing the resonant modes of unique particles and their coupling in simple structures. Numerical algorithms have been developed to extract the phenomenological parameters from the rigorous calculation of the field scattered by the particles. This methodology has been applied to various cases from the single particle to two dimensional particle arrays. The experimental section develops a metallic nanostructures inscription method based on electrolytic reduction of metal ions in meso-porous silica thin film, by applying a voltage between a conductive AFM tip and the conductive substrate supporting the film. Structures are formed on both sides of the silica layer, with the possibility to switch their position by a simple reversal of the applied potential. Moreover, it appears that this switching is accompanied by changes in the local conductivity of the silica layer. A consequence of the inscription process is the formation of metal filaments at the ends of AFM tips. In particular, gold filaments are obtained with sizes ranging from tens to hundreds of nanometers long with a few nanometers thick

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-19T19:31:47Z No. of bitstreams: 1 ligiamariaalvesdelacerda.pdf: 5069586 bytes, checksum: 1d64230fb2ba63a875f3302b83855cce (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-29T12:33:33Z (GMT) No. of bitstreams: 1 ligiamariaalvesdelacerda.pdf: 5069586 bytes, checksum: 1d64230fb2ba63a875f3302b83855cce (MD5) / Made available in DSpace on 2017-06-29T12:33:33Z (GMT). No. of bitstreams: 1 ligiamariaalvesdelacerda.pdf: 5069586 bytes, checksum: 1d64230fb2ba63a875f3302b83855cce (MD5) Previous issue date: 2012-12-11 / Esta pesquisa tem como objetivo analisar as narrativas visuais, vinculadas à memória da indústria gráfica regional, tomando-se como investigação o estudo da implantação da primeira casa litográfica comercial do Estado de Minas Gerais, a Litografia a vapor Pietro Biancovilli. A fonte principal da pesquisa é o Álbum 6 de litografias pertencente ao acervo do Arquivo Histórico da Fundação Museu Mariano Procópio, que contem 130 exemplares de impressos comerciais pertencentes a essa litografia. Buscou-se, também, a análise em fontes documentais encontradas no Setor de Memória da Biblioteca Municipal Murilo Mendes, no Arquivo Histórico de Juiz de Fora e no Arquivo Público Mineiro, onde foram examinados periódicos e documentos relativos à chegada e à produção do litógrafo italiano Pietro Angelo Biancovilli. O recorte temporal se inicia em 1888, quando o emigrante chega ao Brasil, e termina no ano de 1914, quando se encerram suas atividades comerciais. Consoante com as proposições da História Cultural, esta pesquisa concebe o exame das práticas e representações imagéticas, forjadas no âmbito da cidade de Juiz de Fora em fins do século XIX e décadas iniciais do século XX. / This research has the purpose to analize the visual accounts linked to the memory of local graphic industry, studying the settling of the first commercial lithography house in the State of Minas Gerais, the steam litography Pietro Biancovilli. The main source of the research is the “Álbum 6” of lithographies belonging to the collection of the Historical Archive of the Mariano Procópio Museum Foundation, with 130 pieces of commercial prints belonging to this lithography. It has been analized documental sources found in the Memory Department of the Municipal Library Murilo Mendes, in the Historical Archive of Juiz de Fora and in the Public Archive of Minas, where it has been examined periodicals and documents related to the arrival and production of the italian lithographer Pietro Angelo Biancovilli. The time researched begins in 1888, when the foreigner arrives to Brazil, and it ends in the year of 1914, when he closes his commercial activities. Regarding to the propositions of Cultural History, this research conveives the examination of practices and representations of images, forged in the Juiz de Fora life in the end of 19th Century and in the first decades of the 20th Century.

This work deals with fabrication and examination of optical properties of self-ordered TiO2 and Au quantum dots array and its potential usage in medicine as optical sensor for biomolecules detection. Controlled anodization of Ti through Al2O3 template was chosen as a fabrication method for TiO2 QDs, in case of Au galvanic deposition through Al2O3 template onto beforehand prepared TiO2 QDs or substrate with dimple structure. The influence of anodization and deposition conditions on the final structure of QDs and their emission spectrum is also examined.