Journal ArticleDOI
Crystal chemical substitutions and doping of YBa2CU3Ox and related superconductors
TLDR
A review of the literature on substitutions and their effect on the properties of the 90 K superconductor YBa 2 Cu 3 O δ (YBCO) can be found in this paper.Abstract:
The 90 K superconductor, YBa 2 Cu 3 O δ (YBCO), has proved to be highly adaptable chemically as it can accommodate a wide variety of cationic and anionic substitutions. Indeed, the majority of the chemical elements, excluding noble gases and actinides, have been reported to substitute to some extent into the YBCO structure. This review covers the literature on such substitutions and their effect on the properties of YBCO. Reported solubility limits are given, together with crystal symmetry and trends in unit cell parameters with dopant concentration. The dopant site is considered; this is additionally complex in the case of copper substitution because of the two distinct copper sites in the crystal structure. The effect of the dopant on the critical temperature, T c , is reviewed; the literature is often contradictory due to the dual effects of variable oxygen content and the nature of the dopant. Preparation methods appear to have an effect on solubility limits, crystal symmetry and T c , Also, the methods used to determine solubility limits are often imprecise which can lead to contradictions. The magnetic properties of doped materials are reviewed; for some dopants, particularly the magnetic lanthanides, antiferromagnetism and superconductivity co-exist. The related RBa 2 Cu 3 O δ phases (R = lanthanide), their structure, properties and behaviour on doping are reviewed in a similar way. For the larger rare earths, the related systems R 1+ x Ba 2- x CU 3 O δ , are reviewed; as x increases, the transition temperature decreases and compositions R 1.5 Ba 1.5 Cu 3 O δ are semiconducting. The upper and lower solubility limit changes with R, and for R = Dy, the upper limit is x = 0 composition, LaBa 2 Cu 3 O δ , cannot be prepared in air since substitution of La onto the Ba site occurs, forming the Ba-deficient solid solutions. The discovery of superconductivity above liquid nitrogen temperatures in YBa 2 Cu 3 O 7 , has generated a vast quantity of research; to date, > 20 000 papers have appeared on the 123 materials (source: BIDS). This review, therefore, cannot be comprehensive, but attempts to highlight important substitutions, their effect on the properties of YBCO and any contradictions in the literature.read more
Citations
More filters
Journal ArticleDOI
The RABiTS approach: Using rolling-assisted biaxially textured substrates for high-performance YBCO superconductors
TL;DR: In this paper, an overview of the fabrication of epitaxial buffer layers on rolling-assisted biaxially textured substrates (RABiTS) as templates for YBCO films carrying high critical current densities is provided.
Journal ArticleDOI
Transition Metal Oxide Core-Shell Nanowires: Generic Synthesis and Transport Studies
TL;DR: A generic non-equilibrium synthesis technique has been developed to produce novel transition metal oxide nanowires, including YBa2Cu3O6.66, La0.67Ca0.33MnO3, PbZr0.58Ti0.42O3 and Fe3O4.
Journal ArticleDOI
Island growth of Y2BaCuO5 nanoparticles in (211∼1.5 nm/123∼10 nm)×N composite multilayer structures to enhance flux pinning of YBa2Cu3O7−δ films
TL;DR: In this article, a controlled introduction of second-phase Y2BaCuO5 (211) nanoparticles into YBa2Cu3O7−δ (123) thin films was achieved for the purpose of increasing flux pinning.
Journal ArticleDOI
Yttrium barium copper oxide superconducting transition temperature modeling through gaussian process regression
Yun Zhang,Xiaojie Xu +1 more
TL;DR: In this article, the Gaussian process regression model is developed to predict YBCO superconducting transition temperature based on lattice parameters, and the results show a high correlation coefficient (99.78%), a low prediction root mean square error (1.04%) and mean absolute error (0.27%) of the sample mean.
Journal Article
Crystal Structure of Tetragonal YBa_2Cu_ Co_δO_ (δ=0, 0.3)
TL;DR: In this article, the structure of tetragonal YBa2Cu2.7Co 0.3O7-γ was determined by X-ray and TOF neutron powder diffractometries.
References
More filters
Journal ArticleDOI
Possible high Tc superconductivity in the Ba-La-Cu-O system
TL;DR: In this paper, Ba−La−Cu−O system, with the composition BaxLa5−xCu5O5(3−y) have been prepared in polycrystalline form, and samples with x=1 and 0.75,y>0, annealed below 900°C under reducing conditions, consist of three phases, one of them a perovskite-like mixed-valent copper compound.
Journal ArticleDOI
Superconductivity at 93 K in a new mixed-phase Y-Ba-Cu-O compound system at ambient pressure
Maw-Kuen Wu,J. R. Ashburn,C. J. Torng,Pei-Herng Hor,R. L. Meng,Li Gao,Z. J. Huang,Yongmei Wang,Ching-Wu Chu +8 more
TL;DR: A stable and reproducible superconductivity transition between 80 and 93 K has been unambiguously observed both resistively and magnetically in a new Y-Ba-Cu-O compound system at ambient pressure.
Journal ArticleDOI
Bulk superconductivity at 91 K in single-phase oxygen-deficient perovskite Ba 2 YCu 3 O 9 − δ
Robert J. Cava,Bertram Batlogg,R. B. van Dover,Donald W. Murphy,Steven A. Sunshine,Theo Siegrist,J. P. Remeika,Edward A. Rietman,S. M. Zahurak,G. P. Espinosa +9 more
TL;DR: Observation de la transition supraconductrice a 91 K, sur 1,5 K and determination of the densite de courant critique, de l'effet Meissner, du champ critique, du parametre de Sommerfeld, de parametres GL.