Author: Penelope Anne Pullan
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Flux Pinning in Yttrium Barium Copper Oxide Superconducting Thin Films
Author: Penelope Anne Pullan
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Enhancing the Flux Pinning of High Temperature Superconducting Yttrium Barium Copper Oxide Thin Films
Author: Mary Ann Patricia Sebastian
Publisher:
ISBN:
Category : Flux pinning
Languages : en
Pages : 129
Book Description
Publisher:
ISBN:
Category : Flux pinning
Languages : en
Pages : 129
Book Description
Enhanced Flux-Pinning Properties in Superconducting YBa2Cu3O7-[delta] Thin Films with Nanoengineering Methods
Author: Chen-Fong Tsai
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Since the discovery of the high temperature superconductor YBa2Cu3O7-[delta] (YBCO), with transition temperature (Tc = 77 K), above liquid nitrogen point in 1987 many research projects have been dedicated to enhancing the high field performance of this material for practical applications. The 2nd generation YBCO-based coated conductors are believed to be the most promising approach for commercial applications including power transmission, motors, generators, and high field magnets. With the advances of nanotechnologies, different nanoengineering methods have been demonstrated to enhance the performance of YBCO thin films, include doping with 0-dimensional (0-D) self-assembled nanoparticles, 1-dimensional (1-D) nanorods, and 2-dimensional (2-D) nanolayers. Furthermore, dopants with ferromagnetic properties are also reported to provide enhanced pinning effects by Lorentz force, especially under high-applied magnetic fields. The principle of these methods is to generate high-density defects at the heterogeneous interfaces as artificial pinning centers in an effort to improve the flux-pinning properties. The morphology and dimensions of the nanoinclusions play an important role in pining enhancement. Optimized pinning structures are likely to be located at energetically favorable vortex cores, which form a triangular lattice with dimensions close to the YBCO coherence length [xi]([xi]ab ~ 4 nm; [xi]c ~ 0.5 nm at 77 K.) However, it is challenging to achieve small dimensional nanodopants in the vapor deposited YBCO thin films. The purpose of this research is to utilize nanoengineering methods to produce optimized pinning structure in YBCO thin films. In this thesis, we systematically study the effects of different nanoinclusions on the flux-pinning properties of YBCO thin films. The 0-D ferromagnetic Fe2O3 and CoFe2O4 nanoparticles, 2-D CeO2 multilayers, and tunable vertically aligned nanocomposites (VAN) of (Fe2O3)x:(CeO2)1-x and (CoFe2O4)x:(CeO2)1-x systems are introduced into the YBCO matrix as artificial pinning centers. Results suggest that all nanoinclusions showed significant enhancement in the superconducting properties of YBCO. The ferromagnetic pinning centers dominate at high field and low temperature regimes, however, the defect pinning centers dominate at low field and high temperature regimes. The uniquely arranged VAN structure of alternating magnetic and non-magnetic nanophases, which incorporates both high defect density and tunable distribution of magnetic dopants, is believed to be an ideal solution for flux-pinning enhancement. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149478
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Since the discovery of the high temperature superconductor YBa2Cu3O7-[delta] (YBCO), with transition temperature (Tc = 77 K), above liquid nitrogen point in 1987 many research projects have been dedicated to enhancing the high field performance of this material for practical applications. The 2nd generation YBCO-based coated conductors are believed to be the most promising approach for commercial applications including power transmission, motors, generators, and high field magnets. With the advances of nanotechnologies, different nanoengineering methods have been demonstrated to enhance the performance of YBCO thin films, include doping with 0-dimensional (0-D) self-assembled nanoparticles, 1-dimensional (1-D) nanorods, and 2-dimensional (2-D) nanolayers. Furthermore, dopants with ferromagnetic properties are also reported to provide enhanced pinning effects by Lorentz force, especially under high-applied magnetic fields. The principle of these methods is to generate high-density defects at the heterogeneous interfaces as artificial pinning centers in an effort to improve the flux-pinning properties. The morphology and dimensions of the nanoinclusions play an important role in pining enhancement. Optimized pinning structures are likely to be located at energetically favorable vortex cores, which form a triangular lattice with dimensions close to the YBCO coherence length [xi]([xi]ab ~ 4 nm; [xi]c ~ 0.5 nm at 77 K.) However, it is challenging to achieve small dimensional nanodopants in the vapor deposited YBCO thin films. The purpose of this research is to utilize nanoengineering methods to produce optimized pinning structure in YBCO thin films. In this thesis, we systematically study the effects of different nanoinclusions on the flux-pinning properties of YBCO thin films. The 0-D ferromagnetic Fe2O3 and CoFe2O4 nanoparticles, 2-D CeO2 multilayers, and tunable vertically aligned nanocomposites (VAN) of (Fe2O3)x:(CeO2)1-x and (CoFe2O4)x:(CeO2)1-x systems are introduced into the YBCO matrix as artificial pinning centers. Results suggest that all nanoinclusions showed significant enhancement in the superconducting properties of YBCO. The ferromagnetic pinning centers dominate at high field and low temperature regimes, however, the defect pinning centers dominate at low field and high temperature regimes. The uniquely arranged VAN structure of alternating magnetic and non-magnetic nanophases, which incorporates both high defect density and tunable distribution of magnetic dopants, is believed to be an ideal solution for flux-pinning enhancement. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149478
Electrical Transport and Defect Structures in Yittrium-barium-copper-oxide Thin Films
Author: Todd Lanier Hylton
Publisher:
ISBN:
Category :
Languages : en
Pages : 414
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 414
Book Description
Flux Pinning in YBCO Superconductor
Author: David Bostonian Jan
Publisher:
ISBN:
Category : Ferromagnetic materials
Languages : en
Pages : 332
Book Description
Publisher:
ISBN:
Category : Ferromagnetic materials
Languages : en
Pages : 332
Book Description
Effects of Self-assembled Cerium Oxide Nanodots on the Superconducting Properties of Yttrium Barium Copper Oxide (YBCO) Thin Films
Author: Talisha Haywood
Publisher:
ISBN:
Category : High temperature superconductors
Languages : en
Pages : 144
Book Description
Fabricates yttrium barium copper oxide (YBCO) thin films embedded with cerium oxide (CeO2) nanoparticles using pulsed laser deposition (PLD). Studies the effects of CeO2nanodots in the YBCO matrix. Examines varies methods of improving critical current density (J[subscript]c) of high temperature superconductors by flux-pinning, specifically in YBCO.
Publisher:
ISBN:
Category : High temperature superconductors
Languages : en
Pages : 144
Book Description
Fabricates yttrium barium copper oxide (YBCO) thin films embedded with cerium oxide (CeO2) nanoparticles using pulsed laser deposition (PLD). Studies the effects of CeO2nanodots in the YBCO matrix. Examines varies methods of improving critical current density (J[subscript]c) of high temperature superconductors by flux-pinning, specifically in YBCO.
Part I : Growth and Properties of Reactively Coevaporated Superconducting Yttrium-barium-copper-oxide Thin Films. Part II : Amorphous Superconducting/normal-metal Multilayers in Novel Geometries
Author: Vladimir Cort Matijasevic
Publisher:
ISBN:
Category :
Languages : en
Pages : 416
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 416
Book Description
Flux Pinning in Yttrium Barium Copper Oxide Coated Conductors
Author: Zhijun Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 186
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 186
Book Description
Thin Films and Josephson Junctions of Yttrium Barium Copper Oxide
Author: Peter Andrew Rosenthal
Publisher:
ISBN:
Category :
Languages : en
Pages : 430
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 430
Book Description
Sputter Deposition of Yttrium-barium-copper-oxide Superconducting Thin Films
Author: Robert Glenn Florence
Publisher:
ISBN:
Category : Sputtering (Physics)
Languages : en
Pages : 210
Book Description
Publisher:
ISBN:
Category : Sputtering (Physics)
Languages : en
Pages : 210
Book Description