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Showing 1 to 13 of 13 for “"single crystal sapphire"”.
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Single Crystal Sapphire Photonic Crystal Fibers
A single crystal sapphire optical fiber has been developed with an optical cladding that is used to reduce the number of modes that propagate in the fiber. This fiber is the first single crystal sapphire photonic crystal fiber ever produced. Fabrication of the optical cladding reduces the number of …
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Low Modal Volume Single Crystal Sapphire Optical Fiber
… and consistently reducing the diameter of single-crystal sapphire optical fiber (SCSF) below the limits of standard production methods, including the first production of subwavelength-diameter optical fiber (SDF) composed of single-crystal sapphire. The first known demonstration of an …
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Mode Volume Reduction in Single Crystal Sapphire Optical Fibers
… work on the geometry factors selection for single crystal sapphire optical fiber (SCSF) to improve the optical property in sensing applications. Single crystal sapphire fibers were fabricated with a Laser Heated Pedestal Growth (LHPG) system, which was constructed in-house at Virginia Tech. …
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High temperature diffusion bonding of single crystal sapphire to polycrystalline alumina
Includes bibliographical references (pages 76-77).
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High Temperature Corrosion of Single Crystal Sapphire and Zirconia in Coal Gasification and Commercial Glass Environments
… high temperature measurement system utilizes single crystal sapphire as a sensing element. A series of experiments was performed to determine the corrosion resistance of single crystal sapphire and single crystal fully stabilized cubic zirconia at high temperatures in coal slag and soda lime …
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The properties of single crystal sapphire fibers and the polarimetric optical sensor for high temperature measurements
The polarization-maintaining properties of single crystal sapphire fibers are investigated and a polarimetric optical sensor for high temperature measurements is designed. The polarization-maintaining properties of single crystal sapphire fibers are investigated experimentally for different modal …
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Novel Optical Sensors for High Temperature Measurement in Harsh Environments
… (BPDI) technology is proposed and tested using single crystal sapphire material. With a simple mechanically structured sensing probe, in conjunction with an optical spectrum-coded interferometric signal processing technique, the proposed single crystal sapphire optical sensor can measure high …
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Sapphire Based Fiber-Optic Sensing for Extreme High Temperatures
… like a coal gasifier or an airplane engine. Single crystal sapphire has been studied in the last two decades as a candidate for harsh environment sensing task, due to its excellent mechanical and optical properties under extreme high temperature (over 1000°C). In this research, a sapphire …
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Femtosecond-Laser-Enabled Fiber-Optic Interferometric Devices
… point-damage-based Fiber Bragg gratings in single-crystal sapphire fibers, all-sapphire fiber-tip Fabry-Pérot cavity, and in-fiber Whispering-Gallery mode resonator
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Planar tunneling spectroscopy of thin-film Nb, Nb/normal metal and Nb/semiconductor structures
… DC-magnetron sputter deposited Nb on single-crystal sapphire. The DC resistivity was measured as a function of ternperature to evaluate the film quality and determine Tc. The critical temperature was found to monotonically decrease with decreasing thickness, consistent with existing …
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Acoustic Waveguides and Sensors for High Temperature and Gamma Radiation Environment
… In this dissertation, fused quartz and sapphire acoustic waveguides and sensors are developed for high temperature and heavy gamma radiation. The periodic structure, acoustic fiber Bragg grating (AFBG), is the core sensor structure in this dissertation. To better analyze the propagation …
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Preparation and characterization of doped lead zirconate titanate Pb(Zr<sub>x</sub>Ti<sub>1-x</sub>)O₃ films
… coated onto Pt/Ti/SiO₂/Si, RuO<sub>x</sub> and single-crystal sapphire substrates of various thickness and annealed at a range of temperatures and times. The effects of dopants were studied in terms of the Curie temperature, crystal distortion, transformation temperature, microstructure, optical …
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Optical Frequency Domain Reflectometry Based Quasi-distributed High Temperature Sensor
… such as coal gasification, aerospace, etc. Single crystal sapphire is an excellent candidate for construction of harsh environment sensors due to its superior mechanical and optical properties even at temperature beyond 1600°C. The temperature inside a coal gasifier can be as high as 1200°C. …