The world-class Buchans Mining Camp hosts a number of high-grade, low-tonnage volcanogenic massive sulfide (VMS) deposits. The Lundberg and Engine House zones form the lower-grade stockwork to the Lucky Strike deposit and have yet to be mined. A detailed study of the Lundberg and Engine House zones was conducted to establish the stratigraphic setting of the deposits, to determine the petrology of the host volcanic rocks and distribution of alteration facies, and to characterize the mineralization with the goal of improving exploration for polymetallic massive sulfide deposits in the Buchans camp.

The world-class Buchans Mining Camp hosts a number of high-grade, low-tonnage volcanogenic massive sulfide (VMS) deposits. The Lundberg and Engine House zones form the lower-grade stockwork to the Lucky Strike deposit and have yet to be mined. A detailed study of the Lundberg and Engine House zones was conducted to establish the stratigraphic setting of the deposits, to determine the petrology of the host volcanic rocks and distribution of alteration facies, and to characterize the mineralization with the goal of improving exploration for polymetallic massive sulfide deposits in the Buchans camp.

The world-class Buchans Mining Camp hosts a number of high-grade, low-tonnage volcanogenic massive sulfide (VMS) deposits. The Lundberg and Engine House zones form the lower-grade stockwork to the Lucky Strike deposit and have yet to be mined. A detailed study of the Lundberg and Engine House zones was conducted to establish the stratigraphic setting of the deposits, to determine the petrology of the host volcanic rocks and distribution of alteration facies, and to characterize the mineralization with the goal of improving exploration for polymetallic massive sulfide deposits in the Buchans camp.

The world-class Buchans Mining Camp hosts a number of high-grade, low-tonnage volcanogenic massive sulfide (VMS) deposits. The Lundberg and Engine House zones form the lower-grade stockwork to the Lucky Strike deposit and have yet to be mined. A detailed study of the Lundberg and Engine House zones was conducted to establish the stratigraphic setting of the deposits, to determine the petrology of the host volcanic rocks and distribution of alteration facies, and to characterize the mineralization with the goal of improving exploration for polymetallic massive sulfide deposits in the Buchans camp.

[pt] Fotodetectores de infravermelho possuem uma vasta gama de aplicações diretas em diversos setores, desde militar (e.g. visão noturna, orientação de mísseis) até lazer (aparelhos eletrônicos). Especificamente, os fotodetectores baseados em semicondutores III-V são dispositivos que podem ser construídos para selecionar e medir radiação em faixas específicas do espectro eletromagnético. Dentre as figuras de mérito dos fotodetectores um dos grandes desafios está na redução da corrente de escuro. Neste trabalho visamos produzir um dispositivo de InGaAs com geometria planar, que de acordo com a literatura tem como característica apresentar uma baixa corrente de escuro, nesse caso, há necessidade de difusão de um dopante. Estão reportadas neste trabalho todas as etapas, desde o crescimento das amostras até a caracterização do dispositivo final. Com o auxílio de um reator de MOVPE, foram feitas as calibrações das camadas que fazem parte do dispositivo final, bem como as calibrações do processo de difusão do dopante (Zn). Todas as camadas da amostra foram otimizadas individualmente, assim como a profundidade de difusão desejada (1 µm e nível de dopagem de 2x1018 cm−3). Diversas técnicas de processamento e caracterização foram utilizadas ao longo do trabalho para obter o melhor dispositivo possível. Podemos destacar os resultados de fotocorrente e de corrente de escuro, no qual as medidas foram realizadas com variação da temperatura de 77 até 300 K. Foi possível observar no resultado de espectro de fotocorrente um pico em 0,75 eV referente ao InGaAs a 300 K. Este resultado está de acordo com os de diodos de InGaAs feitos usando o método convencional de dopagem do Zn. / [en] Infrared photodetectors have a wide range of direct applications in various sectors, from military (e.g. night vision, missile guidance) to leisure (electronic devices). Specifically, III-V semiconductor-based photodetectors are devices that can be built to select and measure specific ranges of the electromagnetic spectrum. Among the photodetector figures of merit, one of the great challenges is reducing the dark current. In this work we aim to produce an InGaAs device with planar geometry, which according to the literature has the characteristic of presenting a low dark current. This geometry requires a dopant diffusion. This work reports all the steps, from sample growth to final device characterization. With the aid of an MOVPE reactor, the calibrations of the layers that are part of the final device were made, as well as the calibrations of the dopant diffusion process (Zn). All sample layers were individually optimized, as well as, the desired diffusion depth (1 µm and doping level of 2x1018 cm−3). Several processing and characterization techniques were used throughout the work to obtain the best possible device. We can highlight the photocurrent and dark current results, in which the measurements were performed with a temperature variation from 77 up to 300 K. It was possible to observe from the photocurrent spectrum result a peak at 0,75 eV relative to the InGaAs at 300 K. This result is in agreement with those of InGaAs diodes made using the conventional Zn doping method.

The subject of this study is the design of a camera, which has maximum volume of 50 mm x 50 mm x 300 mm, using short infrared wavelength providing Rayleigh criteria. Firstly, the required flux per pixel has been calculated. Throughout these calculations, atmospheric losses have been obtained by MODTRAN program. Also signal to noise ratio has been examined at minimum and maximum integration time intervals. The focal length of the camera has been calculated as it receives 1 m resolution from 8 km distance. Moreover, the lens materials have been used as N-F2, LIF and BaF2 in this six lens system. The design has been done using ZEMAX optical design program and the performance of the system at focal plane was investigated by the help of Seidel aberrations, Modulation transfer Function (MTF), Spot diagram and Optical Path Difference (OPD) fan plot analyses.

Small molecule organic dyes with absorption and emission in the near infrared region (NIR) attracted much attention for various applications such as dye sensitized solar cells, fluorescent guided surgery, stimuli responsive bioimaging and photodynamic therapy. Dyes with high absorption and emission in the NIR region are beneficial for stimuli responsive bioimaging due to the deeper penetration of NIR light, less cell damage, high resolution, and low background autofluorescence from biomolecules. Of the many small molecule dyes, xanthene-based dyes exhibit outstanding photophysical properties and good stimuli response for use in bioimaging applications. However, absorption and emission of the xanthene dyes lie in the visible region, which limit their applications in cellular imaging. Many of the NIR dyes have very poor fluorescence; consequently, an alternative approach to fluorescent imaging is photoacoustic imaging that uses sound waves to generate pictures of deep tissues. In this dissertation, we discuss the utility of xanthene based NIR dyes as photoacoustic imaging contrast agents for multiplex imaging and deep tissue nitric oxide sensing in the drug-induced liver injury. Chapter I discuss the fundamentals of fluorescence and photoacoustic imaging, background of the xanthene dyes and other fluorescent dyes, and the design strategies to develop NIR xanthene-based dyes. Chapter II is based on our approach to the design and synthesis of NIR xanthene-based dyes by C-H bond functionalization, with the first example being Rhodindolizine, which absorb and emits in NIR II or short-wave infrared (SWIR) region. In chapter III, we describe the design and synthesis of thienylpiperidine xanthene-based NIR and shortwave-infrared (SWIR) dyes for the photoacoustic imaging. One dye in particular (XanthCR-880) boasts a strong PA signal at 880 nm with good biological compatibility and photostability, yields multiplexed imaging with an aza-BODIPY reference dye, and is detected at a depth of 4 cm. In chapter IV, we report a series of SWIR dyes based on a dibenzazepine donor conjugated to thiophene (SCR-1, SCR-4), thienothiophene (SCR-2, SCR-5), and bithiophene (SCR-3, SCR-6). We leverage the fact that SCR-1 undergoes a bathochromic shift when aggregated to develop a ratiometric nanoparticle for nitric oxide (NO) (rNP-NO). rNP-NO was used to successfully perform in vivo studies to visualize pathological levels of nitric oxide in a drug-induced liver injury model via deep tissue SWIR photoacoustic (PA) imaging. Chapter V describes another series of xanthene-based dyes with a thiophene ᴫ spacer and several different donors. UV-Vis absorption studies were performed after converting the dyes to the opened form with trifluoracetic acid. These novel XanthCR-TD dyes exhibit absorption maxima in NIR I region from 700 - 900 nm.

Background matching, a form of camouflage, involves species developing patterns and coloration that closely resemble their environment. Humans have utilized camouflage and background matching, particularly in military applications, to reduce detectable characteristics, known as signatures. Recent advancements in sensor systems necessitate the development of effective camouflage in the short-wave infrared (SWIR) range (0.9 – 2.5 µm). However, absorption of SWIR radiation is heavily influenced by water, and dry textile materials may be easily detectable against a forest background due to their low water content. To address this challenge, this master's thesis explores the integration of hydration onto a textile fabric to reduce the signature in SWIR. Various fabric types were included in this study. The optical properties of these textiles, both when wet and dry, were evaluated using SWIR imaging and UV-VIS-NIR spectroscopy, and compared to foliage. Surface modifications were employed to introduce hydrophobic properties to the fabric, such as the application of water-repelling agents (Nikwax and OrganoTex) or functionalized silica nanoparticles. The water evaporation rates of untreated and surface-treated fabrics were assessed. However, the hydrophobic surface did not significantly reduce water evaporation from the fabrics. Similarly, the addition of a nanocellulose-based hydrogel on the fabric surface did not result in a significant change in evaporation. Combining the hydrogel with water-repelling solutions in a multilayer configuration indicated prolonged evaporation, but further tests are required to validate this finding. This master's thesis demonstrates that introducing water into a dry textile fabric alters its spectral properties, making it more similar to foliage. However, the primary challenge lies in retaining water within the material for improved camouflage in SWIR wavelengths.

As individual health monitors continue to become more widely adopted in helping individuals make informed decisions, new technologies need to be developed to obtain more biometric data. Spectroscopy is a well-known tool to gain biological information. Traditionally spectrometers are large and expensive making personal or wearable health monitors difficult. Here we present the development and characterization of a miniaturized short wavelength infrared spectrometer for wearable applications. We present a carbon nanotube parallel hole collimator can effectively select a narrow set of allowed angles of light to be separated by a linear variable filter and detected at a photodiode array making a spectrometer. We will go over the calibration of the spectrometer showing a resolution of 13 nm at 1300 nm. Improvements on the original collimator data will be discussed, including carbon nanotube growth without infiltration and growth on transparent substrates. We will also show measurements made on human subjects yielding a pulse.

Efficient absorption of light is required for a large number of applications such as thermo-photovoltaics,thermal imaging, bio-sensing, thermal emitters, astronomy, and stealth technology. Strong light absorbers found in nature with high intrinsic losses such as carbon black, metal-black, and carbon nano-tubes etc. are bulky, not design-tunable and are hard to pattern for micro- and nano- devices. We developed thin-film, high performance absorbers in the visible, near-, mid-, long-wave - and far-IR region based on a 3 layer metal-dielectric-metal (MDM) structure. We fabricated a 3-layerMDMabsorber with large band-widths in the visible and near IR spectral range without any lithographic patterning. This was the first demonstration in the optical range of the Salisbury Screen, which was originally invented for radar absorption. A Fabry-Perot cavity model depending on the thickness of the dielectric, but also the effective permittivity of the semi-transparent top metal gives calculated spectra that agree well with experiment. Secondly, we fabricated long-wave IR and far-IR MDM absorbers comprising surface patterns of periodic metal squares on the dielectric layer. Strong absorption in multiple bands were obtained, and these depended weakly on polarization and angle of incidence. Though such absorbers had been extensively studied by electrodynamic simulations and experiment in the visible to far- R regions, there existed no analytic model that could accurately predict the wavelengths of the multiple resonances. We developed a theoretical model for these absorbers based on standingwave resonances, which accurately predicts resonance wavelengths for experiment and simulation for the first time. Unlike metamaterial theories our model does not depend on the periodicity of the squares but only on their lateral dimension and the thickness of the dielectric. This feature is confirmed by synchrotron-based IR spectral imaging microscopy of single isolated squares.