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High Temperature Superconducting Motors
Published in Ranjan Vepa, Electric Aircraft Dynamics, 2020
Yttrium barium copper oxide (YBCO) is a family of crystalline chemical compounds known for exhibiting high-temperature superconductivity. This family of superconductors includes the first material that was discovered to become superconducting above the boiling point of liquid nitrogen (77 K) at about 93 K. Typically, YBCO has a layered structure consisting of copper–oxygen planes with yttrium and barium atoms in the crystal structure as well. The resulting crystal structure is similar to a perovskite, with a unit cell consisting of stacked cubes of BaCuO3 and YCuO3.
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Published in David A. Cardwell, David C. Larbalestier, I. Braginski Aleksander, Handbook of Superconductivity, 2023
YBCO, despite the other superconducting compounds with higher critical temperatures, is now the most promising material for applications aimed to operate either at 77 K or at lower temperatures in high field. It is currently being used in cable manufacture and applications such as power transformers [7]. This enhanced performance of YBCO arises from a structural element unique to this system, linear chains of Cu–O extending in the b-direction. These, and their effects, are discussed in more detail below.
Fuzzy logic laser deposition superconductor production
Published in Patrick H. Garrett, High Performance Instrumentation and Automation, 2018
Yttrium barium copper oxide (YBCO) is a ceramic superconductor material with a unit cell structure shown in Figure 11.3 having a critical temperature of 92 K. The ideal compound, YBa2Cu3O685, is sensitive to stoichiometric and morphologic variations that benefit from the processing capabilities inherent in laser deposition apparatus directed by hierarchical process control methods for consistent manufacture.
High-temperature thermoelectric properties of (1-x)DyBCO − xBNT ceramics
Published in Journal of Asian Ceramic Societies, 2022
Paitoon Boonsong, Anucha Watcharapasorn
Misfit-layered cobalt-based oxide semiconductors were reported to exhibit large and considered to be good candidates for thermoelectric materials [5–8]. Because of the strong electron–electron correlation in these layered Co oxides, there is a possibility for obtaining good thermoelectric properties in these compounds by optimizing the electrical properties and reducing the thermal conductivity. Layered YBa2Cu3O7-δ (YBCO or Y-123) material, which is another typical strong electron correlation layered oxide, have been known as a high-Tc superconductor. In addition, Y-123 is considered a potential oxide thermoelectric material due to its high , moderately high and low [9–13]. The maximum of YBCO was reported to be around 0.3–0.7 [9–13] and its electrical and thermal transport properties was significantly related to oxygen deficiency (δ) in the lattice. It is well known that Y-123 is an oxide compound whose crystal structure is composed of rocksalt and perovskite units. In these materials, the free charge carriers are confined to the planar Cu–O sheets that are separated by insulating layers. The interaction of the special crystal structure leads to the strong anisotropy of electrical conduction which makes these compounds very interesting for thermoelectric properties investigation. REBa2Cu3O7–δ (RE = Nd, Sm, Eu, Gd, Dy, etc.) have better applicability compared to Y-123 system [14–18]. They show a higher metallic-superconducting transition temperature, better surface morphology and also better performance under external magnetic field.
Terahertz absorption properties of YBa2Cu3O7−δ superconductor: thin films grown using a nontoxic, simple spin-coating method
Published in Phase Transitions, 2021
Arata Yasuda, Katsuhiko Moriya, Sou Takahashi, Sota Abiko, Yuki Narita, Gakuto Abe, Kunihiko Tanaka, Tetsuo Sasaki
YBa2Cu3O7−δ (YBCO) is a popular type II superconductor material. Its crystalline structure is of a perovskite type with a CuO plane; it is known to provide a carrier conduction path in YBCO crystals. Many researchers hypothesized that this conduction path plays an important role in the superconduction mechanism in YBCO and other Cu oxide superconductors. However, even after 30 years of research, this phenomenon remains poorly understood [1–3].
Influence of Y2Cu2O5 nanoparticles doping on superconducting properties of YBa2Cu3O7-δ
Published in Phase Transitions, 2019
Chemical doping of high-temperature superconductors (HTSC) by additive or substituent has been a routine way to alter the superconductor’s properties. YBa2Cu3O7-δ (YBCO) has been a superconductor which can be synthesized in a large scale easily and purely and has a crucial role in developing of superconducting wires and tapes so could be a suitable superconductor for industrial applications. Low critical current density of HTSC in the magnetic fields has been a serious HTSCs problem so the enhancement of critical current density has been one of the challenging issues for researchers in this area. The small coherence length, granular feature, weak links at grain boundaries and the weak flux pinning strength have been the most important restricting factors in reducing the critical current of HTSCs [1]. Although many ways have been proposed and solved, some problems like melt process fabrication which can reduce the weak links at grain boundaries [2], but it seems finding new ways to solve the problem of enhancing the critical current density in HTSCs is necessary. The critical current Jc is sensitive to the microstructure of HTSCs and by increasing the magnetic flux pinning centers increased [3], so by introducing nanoscale size of non-superconducting dopant into the superconducting grains, one can improve the Jc of HTSCs. At the beginning of the superconducting researches, it had been shown that by doping of YBCO superconductor by micrometer-sized Y2BaCuO5 (Y211) particles, the critical current could be somewhat improved [4] and the microcracks reduced [5]. So it was a creative impression to increase the Jc of HTSCs by doping them with nanoparticles in the range of coherence length of HTSCs [6]. By rapid development of science in the synthesis of different kinds of the nanomaterials, one can dope the superconductors by nanomaterials to increase the number of flux pinning centers and hence the critical current density of HTSCs materials. Various nanoparticles have been successfully doped in superconductors via sintering process which caused significant enhancement in their critical current density [7,8].