Effects of alkali cation (Li, Na, K, Cs) substitution on the magneto-electrical properties of Y1Ba2Cu3O7−y granular superconductors

Ausloos, Marcel; Laurent, C.; Vanderschueren, Hyacinthe; Rulmont, A.; Tarte, P.

doi:10.1016/0038-1098(88)90200-1

Cited by 29 publications

(9 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This indicates that the magnetic character of Nd suppresses orthorhombic structure much faster than the non-magnetic La substitution for Ba in RBCO. The lattice parameters of pure NdBCO and ErBCO are in good agreement with the reported values [3,4,7].…”

Section: Resultssupporting

confidence: 89%

“…An enormous amount of work has been reported on the effect of cation and anion substitutions in different sublattices of the YBa 2 Cu 3 O z (YBCO) type high-T c superconductors [2-13] with 6.45 < z < 7.15. A family of isostructural materials with rare earth magnetic ions such as Nd 3+ (J = 9/2), Dy 3+ (J = 15/2), Ho 3+ (J = 8), Gd 3+ (J = 7/2) and Er 3+ (J = 15/2) substituted for the Y site exhibited only minor changes in T c [3,4] as there are no oxygen atoms in the R = Y layer whereas the tetravalent dopant Hf 4+ for R = Y and Er showed a decrease in T c [5,6]. This indicates that 100% doping of the Y site by magnetic species such as R = Nd 3+ , Gd 3+ , Er 3+ , Dy 3+ and Ho 3+ does not destroy superconductivity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

Pansuria¹,

Kuberkar²,

Baldha³

et al. 1999

Supercond. Sci. Technol.

View full text Add to dashboard Cite

The structural and superconducting properties of Nd-and Ca-substituted (Nd 1−x Ca x )(Ba 2−y Nd y )Cu 3 O z samples prepared under identical conditions have been investigated by x-ray diffraction, resistivity, ac susceptibility and oxygen content measurements. The effect of increasing Nd concentration in NdBa 2−y Nd y Cu 3 O z lowers the carrier concentration and decreases T c , which is attributed to magnetic pair breaking by local moments and hole filling by Nd. This suppression in T c has been compensated by appropriate hole doping with Ca in (Nd 1−x Ca x )(Ba 2−y Nd y )Cu 3 O z , which shows that for a fixed Nd content at the Ba site T c increases dramatically as the Ca content increases. For instance, in the oxide (Nd 1−x Ca x )(Ba z−y Nd y )Cu 3 O z , the T c increases from 0.0 K (x = 0.0, non-superconductor) to 77.5 K (x = 0.4, compensated oxide) as the magnetic pair breaking and hole filling by Nd is nearly balanced by hole doping from Ca.

show abstract

Section: Resultssupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

Pansuria¹,

Kuberkar²,

Baldha³

et al. 1999

Supercond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…The substituted monovalent Na' ions for divalent Ba2' ions in Y B a 2 C ~3 0 7 -6 are expected to introduce changes in the crystal structure and the density of states. The unit cell for the YBa1,95Na0,05C~307-6 ceramic, which is close to the YBal,9Nao,lCu307-6 sample (Y-Ba-Na-Cu-0 hereafter) investigated here, is orthorhombic (Ausloos et al 1988). The pure and doped Y B a 2 C ~3 0 7 -6 samples display superconducting properties in the orthorhombic phase, in contrast to these samples in the tetragonal phase, in which no superconductivity is observed (Jorgensen et a1 1987).…”

Section: Introductionsupporting

confidence: 60%

An EPR investigation of the high-T_csuperconductor YBa_1.9Na_0.1Cu₃O_7-δ

Misra

Misiak

1989

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

X- and Q-band electron paramagnetic resonance studies have been carried out on a polycrystalline superconductor YBa1.9Na0.1Cu3O7- delta (Y-Ba-Na-Cu-O) over the temperature range 4.2-300 K. It is concluded that the monovalent Na+ ions substitute for Ba2+ ions, and not for Cu2+ ions. The onset of the superconducting transition is determined to occur at 91 K, while the absorption of microwaves in low magnetic fields begins to occur below 100 K. The value of the upper critical field estimated here, as well as that of the specific heat coefficient are lower than those reported for the pure YBa2Cu3O7- delta ceramic. The local symmetry about the Cu2+ ion in the phase of the sample with increased oxygen vacancy content, responsible for the Cu2+ EPR signal, is deduced to be orthorhombic over the entire range of temperature investigated, as revealed by the Cu2+ principal values (gz, gx and gy), which are, in turn, used to estimate the energy-level sequence for the Cu2+ ion. The covalency effect due to Cu-O bonding is found to be significant. The hyperfined splitting constant mod Az mod , as estimated from the weak hyperfine structure at low magnetic fields, is estimated to be 8 mT at 4.2 K. The sample exhibits magnetic memory in the superconducting state.

show abstract

“…IV C 2). Alkali metals again are practically the only candidates, and minute amounts of K, Rb and Cs are reported either at the Ba site [611] or at both the Y and Ba sites in YBa2Cu306+w [105,612]. Somewhat surprisingly, no incorporation of Pb at the Ba site is found, and a different (although 123-related) structure is in fact formed when PbO is introduced into the Y(O)-Ba(O)--Cu(O) system [613,614].…”

Section: Metals Except Aes and Resmentioning

confidence: 98%

Phase diagrams for the YBa2Cu3O7 family — ANNO 1996

Karen

Kjekshus

1997

Journal of Thermal Analysis

View full text Add to dashboard Cite

Phase diagrams for cupratcs of alkaline earth and rare earth elements are presented, covering binary to quintenary oxides and including selected solid solution series with other elements. Elementary crystal chemical data are included for identification of the occurring phases. Chemical stability is discussed with respect to the high-temperature reactions with Lewis acids like CO2, protons, etc. Particularly the occurrence of oxide carbonates is consistently pointed out as one of the possible reasons for contradictory results in phase diagrams which comprise oxides with high basicity.

show abstract

Effects of alkali cation (Li, Na, K, Cs) substitution on the magneto-electrical properties of Y1Ba2Cu3O7−y granular superconductors

Cited by 29 publications

References 14 publications

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

An EPR investigation of the high-T_csuperconductor YBa_1.9Na_0.1Cu₃O_7-δ

Phase diagrams for the YBa2Cu3O7 family — ANNO 1996

Contact Info

Product

Resources

About

Effects of alkali cation (Li, Na, K, Cs) substitution on the magneto-electrical properties of Y1Ba2Cu3O7−y granular superconductors

Cited by 29 publications

References 14 publications

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa2Cu3Oz

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa2Cu3Oz

An EPR investigation of the high-Tcsuperconductor YBa1.9Na0.1Cu3O7-δ

Phase diagrams for the YBa2Cu3O7 family — ANNO 1996

Contact Info

Product

Resources

About

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

Influence of hole filling and pair breaking by Nd and hole doping by Ca on the superconductivity of NdBa₂Cu₃O_z

An EPR investigation of the high-T_csuperconductor YBa_1.9Na_0.1Cu₃O_7-δ