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Showing 1 to 20 of 45 for “"YbA"”.
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Thermodynamics of oxygen ordering in YBa₂Cu₃O₆₊
… used to study the thermodynamics of oxygen in YBa2Cu306+x in order to help determine the correct model for oxygen thermodynamics as well as to provide standard curves for materials preparation by other methods. In particular, extensive measurements have been made on the oxygen pressure …
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Solid solubility of silver in the superconducting YBa₂Cu₃O compound
The solubility of silver in the YBa₂Cu₃Ox compound has been studied. Ceramic YBa₂Cu₃Ox pellets with added silver ranging from 0 to 10 wt% were prepared and characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), …
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Radio-frequency properties of melt-recrystallized YBa₂Cu₃O₇â[delta] fibers
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994.
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Microstructural control and superconducting properties of YBa₂Cu₃O₇₋ₓ melt textured single crystals
… are desired. To achieve the goal in fabricating YBa₂Cu₃O₇₋ₓ(Y123) samples suitable for the applications, detailed and systematic studies are required to gain further understanding of the crystal growth and flux pinning mechanisms. This research is aimed at constituting a contribution to the …
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Depinning do fluxo de Josephson em compósitos YBa 2 Cu 3 O 7-delta/Ag
Apresenta-se neste trabalho um estudo experimental da dinâmica do fluxo magnético intergranular no cuprato supercondutor Y Ba2Cu3O7 e nos compósitos Y Ba2CU3O7 fi/Ag para várias concentrações de prata. Verificou-se que sob certas condições é possível separar os efeitos da dinâmica do fluxo de …
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[mu]SR measurement of the magnetic penetration depth and coherence length in the high-T superconductor YBa₂Cu₃O₆ 95
… K A/e in the high temperature superconductor YBa2Cu306.95 as observed by OR measurements of the local field inhomogeneity produced by the vortex state. Measurements were taken on a mosaic of single crystals in applied fields in three field regimes: low (A < L), moderate (A > L) and high (A > L …
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Thermal Conductivity of Tl(2)Ba(2)CuO(6+delta) and Fluctuation Diamagnetism of YBa(2)Cu(3)O(6+x)
The increased contribution of the fluctuation signal to the magnetization over a wide temperature range is clearly evident in the more anisotropic samples. Within the anisotropic-effective-mass 3D-XY model, the change in anisotropy with reduced transition temperature is directly related to the …
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I. An oxygen-17 NMR study on oxygen exchange in yttrium barium(2) copper(3) oxygen(7-x). II. Synthesis of transition metal polysulfide complexes from metal powders
… (T$\sb{\rm c}$ = 1.66 K) and $\rm YBa\sb2Cu\sp{II}\sb2Cu\sp{III}O\sb{7-x}\ (T\sb{c}$ = 92 K) are similar in that both are superconductors containing layered structures and mixed valent copper centers. Our studies on YBa$\sb2$Cu$\sb3$O$\sb{\rm 7-x}$ focused on $\sp{17}$O-labelling of …
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Low-temperature specific heat of several high-temperature superconductors in the superconducting and mixed states
… Ba$\sb{0.6}$K$\sb{0.4}$BiO$\sb3,$ YBa$\sb2$Cu$\sb3$O$\sb{6.7},$ and Bi$\sb2$Sr$\sb2$CaCu$\sb2$O$\sb{\rm 8+x}$ were measured in the superconducting state. Careful analysis of the data below 10K indicate that the contribution to the specific heat which has a linear dependence on …
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Oxygen-17 nuclear magnetic resonance studies of high-temperature superconductors
… La$\sb{1.85}$Sr$\sb{0.15}$CuO$\sb4$, YBa$\sb2$Cu$\sb3$O$\sb{\rm 7-x}$, Bi$\sb2$Sr$\sb2$CaCu$\sb2$O$\sb8$ and Tl$\sb2$Ba$\sb2$CaCu$\sb2$O$\sb8$. Measurements of the angular dependence of the oxygen frequency shifts and corresponding satellite transitions have enabled us to assign the …
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Interlayer optical response of yttrium barium (copper (cobalt, zinc)) oxide
… dielectric responses of chain substituted $\rm YBa\sb2Cu\sb3O\sb{6 + x}$ and $\rm YBa\sb2(Cu\sb{1 - y}Co\sb{y})\sb3O\sb{6 + x}$ and of plane substituted $\rm YBa\sb2(Cu\sb{1 - y}Zn\sb{y})\sb3O\sb{6 + x}.$ A dramatic decrease in the low-frequency c-axis optical conductivity, $\sigma\sb{\rm …
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Composition dependence of superconductivity in YBa₂(Cu<sub>1-x</sub>A<sub>x</sub>)₃O<sub>6+δ</sub> system with A = Zn, Ni
… Cu are presented in the high Tc superconductors, YBa₂(Cu<sub>1 - x</sub>A<sub>x</sub>)₃O<sub>6 + δ</sub> where x < 0.03 for Zn and x< 0.10 for Ni. We have observed that the superconducting temperature in the high Tc YBa₂Cu₃O<sub>6 + δ</sub> as system decreases if copper is substituted by Ni and Zn …
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Modifying the Composition of a High Temperature Superconductor
… research was to recreate a known superconductor, YBa<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub>, and modify it in an attempt to raise its transition temperature. A superconductor is any material that excludes magnetic flux from its interior when at a temperature below its transition temperature. A …
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Tuning the properties of high-Tc superconductor & Sr2IrO4, and exploring transport through single nanocrystals
… study of high-temperature superconductor YBa$_2$Cu$_3$O$_{7-\delta}$, the ionic-liquid gating study of the Mott insulator Sr$_2$IrO$_4$, and the single-electron study of quantum dot device with self-assembled nanocrystal PbS. Chapter 1 covers a general introduction to all three projects. …
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Single crystal NMR of high-temperature superconductors
… studies of the high temperature superconductor YBa$\sb2$Cu$\sb3$O$\sb{7-\delta}$ (T$\sb{\rm c}$ = 90K) using a 1 mg single crystal.
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