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Showing 1 to 20 of 113 for “"High temperature superconductors"”.
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Critical current anisotropy in high temperature superconductors
After nearly 15 years of research effort, High Temperature Superconductors (HTS) are finding a wide range of practical applications. A clear understanding of the factors controlling the current carrying capacity of these materials is a prerequisite to their successful technological development. The …
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Single crystal NMR of high-temperature superconductors
The author reports Cu NMR 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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Light scattering on the high-temperature superconductors
The high temperature superconductors have been examined by the technique of Raman scattering in several limits: the insulating phase, the normal and superconducting state of the superconducting phase, and an optically induced metastable phase. In all cases, the analysis and proposed …
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Power-law liquid in high-temperature superconductors
… we demonstrate that the normal state of cuprate superconductors can be described by a power-law liquid, a state of matter with a power-law self-energy $\Sigma^{\pr\pr}\sim(\omega^{2}+\pi^{2}T^{2})^{\alpha}$. The scaling exponent decreases from $\alpha\sim1$ in the overdoped Fermi-liquid state to …
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Critical currents in granular high temperature superconductors
… current density (Jc) of several different high temperature superconductors (HTSCs) as a function of temperature and applied magnetic field. The focus of this research has been to investigate the discrepancies which generally exist between magnetic and transport measurements on HTSCs. In …
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Electron Tunnelling Study of High-Temperature Superconductors
… between June 1987 and October 1991, in the Low Temperature Physics Group at the Cavendish Laboratory, Cambridge. The aim of this work was to use electron tunnelling spectroscopy to measure the density of excitation states of the recently discovered high-temperature superconductors. Tunnelling is …
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Topics in the Theory of High -Temperature Superconductors
The second scenario which we examine is the SO(5) theory of superconductivity, which attempts to unify the antiferromagnetic and superconducting regions of the phase diagram. We propose and theoretically explore experiments designed to test the SO(5) scenario.
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Electronic Noise Studies of Underdoped High Temperature Superconductors
… in order to probe normal state properties of high temperature superconductors with the goal of providing further detail about the environment in which the necessary pairing of electrons occurs. We observe an unusual noise component near and below about 200 K in the normal state of underdoped …
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Topics in the Theory of High-Temperature Superconductors
… the origin of superconductivity in the hightemperature cuprate superconductors lies in the intriguing properties of the global phase diagram of the cuprate materials. In particular, strongly underdoped cuprates exhibit antiferromagnetic order, whereas moderately underdoped cuprate …
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Stability and quench protection of high-temperature superconductors
… reliability and safe operation. Although the high-temperature superconductor (HTS) is considered much more stable than the low-temperature superconductor (LTS), it is susceptible to damage caused primarily by three events that can occur in large-scale "real" devices: 1) overheating; 2) high …
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Computational modelling of the vortex state in high-temperature superconductors
The vortex state in high temperature superconductors is investigated using computer simulations. Vortices are represented as particles and we employ Langevin dynamics to study the statics and dynamics of the system.<br/><br/>We show that the long-range nature of the vortex-vortex interaction can …
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Low Energy Electronic Raman Scattering in Cuprate High Temperature Superconductors
The temperature dependence of the 2$\Delta$-peak in overdoped Tl-2201 implies that the superconducting gap opens very rapidly below the critical temperature. The measured peak intensity as a function of temperature, however, shows an anomalous behavior. A magnetic field is observed to affect Raman …
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Oxygen-17 nuclear magnetic resonance studies of high-temperature superconductors
… and magnetically oriented samples of various high-$T\sb{c}$ superconductors. Systems under investigation include: (BaK)BiO$\sb3$, 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 …
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The competitive potential of high-temperature superconductors for power transmission
High temperature superconductors were discovered in 1987. World-wide, many groups are presently engaged in the research and development of these materials for power transmission cable applications. This thesis examines the competitive potential, on a cost-performance basis, of high-temperature …
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Electronic properties of doped Mott insulators and high temperature superconductors
High-temperature superconducting cuprates, which are the quintessential example of a strongly correlated system and the most extensively studied materials after semiconductors, spurred the development in the fields of material science and experimental and theoretical physics. As first noted by …
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Magnetic, DC transport, and microwave properties of high temperature superconductors
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1994.
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Superconductor-insulator transition induced by electrostatic charging in high temperature superconductors.
… films were grown on SrTiO3 substrates in a high pressure oxygen sputtering system to study the superconductor-insulator transition by electrostatic charging. While backside gating using SrTiO3 as a dielectric induces only small TC shifts, a clear transition between superconducting and …
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Electrical characterization of high temperature superconductors as a function of temperature
… Bi 2Sr 2Ca2 Cu3010 (BSCCO- 2223/Ag) tapes at temperatures ranging from 77 K to 110 K were measured using a typical four-terminal technique for two different BSCCO-2223/Ag tapes manufactured by Vacuumschmelze (VAC). The critical currents for the two VAC samples were measured as a function of …
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High-temperature superconductors as electromagnetic deployment and support structures in spacecraft
… technique uses the magnetic fields generated by high-temperature superconductors (HTSs) to support spacecraft structures and deploy them to operational configurations from stowed positions inside a launch vehicle fairing. The chief limiting factor in spacecraft design today is the prohibitively …
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Visualizing Cooper Pair Formation on the Atomic Scale in High Temperature Superconductors
… in cuprates, one hotly debated issue is the temperature at which Cooper pairs first form. Do pairs form at the critical temperature Tc or do they form at higher temperatures lacking phase rigidity? To answer the question, we have developed new techniques, based on scanning tunneling …
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