Oxygen determination from cell dimensions in YBCO superconductors

Benzi, Paola; Bottizzo, Elena; Rizzi, N.

doi:10.1016/j.jcrysgro.2004.05.082

Cited by 127 publications

(43 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…YBCO single crystals have an even smaller c-axis lattice constant (c bulk = 1.167(1) nm). 24 A lower defect density is generally expected in single-crystal YBCO compared to thin-film YBCO which is consistent with the trend of the c-axis lattice constants. From this point of view YBCO Au has a lower defect density than our pristine YBCO, but a higher one compared to single-crystal YBCO.…”

supporting

confidence: 76%

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

et al. 2014

View full text Add to dashboard Cite

Adding Au nanoparticles to YBa2Cu3O 7−δ thin films leads to an increase of the superconducting transition temperature Tc and the critical current density jc. While the higher jc can be understood in terms of a stronger pinning of the flux vortices at the Au nanoparticles, the enhanced Tc is still puzzling. In the present study, we determined the microscopic magnetic penetration profiles and the corresponding London penetration depths λL in the Meissner state of optimally doped YBa2Cu3O 7−δ thin films with and without Au nanoparticles by low-energy muon spin rotation. By Rutherford backscattering spectrometry, we show that the Au nanoparitcles are distributed over the whole thickness of the thin-film samples. The superfluid density ns ∝ 1/λ 2 L was found to increase in the films containing Au nanoparticles. We attribute this increase of ns to a reduction of the defect density possibly due to defect condensation at the Au nanoparticles.The influence of disorder on cuprate systems is still an open issue. It is known that disorder directly affects the superconducting properties of these systems, but the underlying mechanisms are not fully clarified. 1 In YBa 2 Cu 3 O 7−δ (YBCO), for instance, the charge carrier transfer from the Cu-O chains to the CuO 2 planes is crucial for the appearance of superconductivity. This charge transfer depends strongly on the oxygen order and on the oxygen mobility within the Cu-O chains. 2 Substitution of chain Cu by other metal ions leads generally to a suppression of the superconducting transition temperature T c . 3 Surprisingly, this does not apply to Au. Superconducting quantum interference device (SQUID) and neutron diffraction measurements performed by Cieplak et al. 4,5 show that it is possible to incorporate 10 at.% Au into the structure of polycrystalline YBCO, where Au exclusively replaces the chain Cu(1) atoms. This leads to an increase of T c of about 1.5 K and to an increase of the c-axis lattice constant. The Cu-O bond length between Cu(1) and the oxygen in the Cu-O chains as well as between Cu(1) and the bridging oxygen are enlarged. Previous studies revealed also a lower normal state resistance and a minor influence on the normal state magnetization and on the upper critical field. 6 Recently, it has been demonstrated that Au nanoparticles, incorporated in YBCO thin films, lead to an increase of T c and the critical current density j c (from 4 · 10 7 A/cm 2 to 6 · 10 7 A/cm 2 at 10 K). 7,8 Since YBCO is superconducting above the boiling temperature of nitrogen this is of special interest for applications. A stronger flux pinning of the vortices at the Au nanoparticles causes a higher j c , which is crucial in order to improve superconducting magnetic field sensors 8,9 as used in dc-SQUID gradiometers.Until now little is known about the effect of the inclusion of Au nanoparticles on the microscopic superconducting parameters, such as the superfluid density n s . In the present study we investigated two sets of YBCO thin films with different Au contents by means of low-e...

show abstract

supporting

confidence: 76%

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The change in c is mainly caused by the change in d Cu(2)-O(4) because it is much more sensitive to change in the oxygen content than other bond lengths. The lattice parameter c can be easily measured to high precision by diffraction techniques and there has been considerable work [7][8][9][10][11][12] on the relationship between c and the oxygen content of YBCO. However, by examining the data for our single crystals we have found that the dependences of p and c on the oxygen content are not unique: both p and c depend not only on the oxygen content but also on the degree of oxygen ordering in the Cu(1)-O chains.…”

mentioning

confidence: 99%

Evaluation ofCuO2plane hole doping inYBa2Cu3O6+x
Liang
¹
,
Bonn
²
,
Hardy
³

2006
Phys. Rev. B
373
44
380
1
View full text Add to dashboard Cite

The electron hole concentration p in the CuO 2 planes of YBa 2 Cu 3 O 6+x (YBCO) has been evaluated using the unit cell length in the c-direction together with a simple estimation for p in the chain oxygen ordered phases. The empirical relationship between p and c obtained allows calculation of p from the caxis lattice parameter for the entire doping range of YBCO. It is also suggested that the empirical parabola describing the relationship between T c and p in La 2-δ Sr δ CuO 4 is reasonably correct for YBCO except for the region around p =1/8, where the T c of YBCO is suppressed by as much as 17 K. A correction of the parabola for the p = 1/8 effect is presented.

show abstract

“…3. It is clear that the 007 peak of YBCO shifts regularly to lower 2y values from S1 to S4, implying an expansion of the out-of-plane lattice parameter c. A similar variation of c as a function of O vacancy concentration is well known for bulk YBCO [1] and is used as a rapid and nondestructive way to determine d in bulk YBCO specimens [8]. Some additional effects are expected to modify the relations presented in Fig.…”

Section: Resultsmentioning

confidence: 59%

Microstructural changes in epitaxial YBa2Cu3O7−δ thin films due to creation of O vacancies

Kuru

Usman

Cristiani

et al. 2010

Journal of Crystal Growth

View full text Add to dashboard Cite

Oxygen determination from cell dimensions in YBCO superconductors

Cited by 127 publications

References 29 publications

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

Evaluation ofCuO2plane hole doping inYBa2Cu3O6+x
Liang
¹
,
Bonn
²
,
Hardy
³

2006
Phys. Rev. B
373
44
380
1
View full text Add to dashboard Cite

Microstructural changes in epitaxial YBa2Cu3O7−δ thin films due to creation of O vacancies

Contact Info

Product

Resources

About

Oxygen determination from cell dimensions in YBCO superconductors

Cited by 127 publications

References 29 publications

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

Modifications of the Meissner screening profile in YBa2Cu3O7−δthin films by gold nanoparticles

Evaluation ofCuO2plane hole doping inYBa2Cu3O6+xLiang1, Bonn2, Hardy3 2006Phys. Rev. B373443801View full textAdd to dashboardCite

Microstructural changes in epitaxial YBa2Cu3O7−δ thin films due to creation of O vacancies

Contact Info

Product

Resources

About

Evaluation ofCuO2plane hole doping inYBa2Cu3O6+x
Liang
¹
,
Bonn
²
,
Hardy
³

2006
Phys. Rev. B
373
44
380
1
View full text Add to dashboard Cite