Josephson vortices and flux penetration in high temperature superconductors

Müller, K.‐H.; Macfarlane, J.C.; Driver, R.

doi:10.1016/0921-4534(89)90298-0

Cited by 123 publications

(29 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On these hypotheses, the response of the sample is even during the period of the em field; consequently, only odd-harmonic emission is expected. Even harmonics can be expected by taking into account the field dependence of the critical current [18,19], according to the Anderson and Kim critical state model [26]. However, for H dc ≫ H ac the results obtained by using the Anderson-Kim model converge to those of Bean and only odd harmonics are expected [18].…”

Section: Discussionmentioning

confidence: 85%

“…Several mechanisms give rise to emission of signals oscillating at harmonic frequencies of the driving field. At low magnetic fields and low temperatures, harmonic generation has been ascribed to nonlinear processes in weak links, impurities and intergrain-fluxon dynamics [17,18,19,20]. At magnetic fields higher than the lower critical field, when the weak links are decoupled, harmonic emission has been ascribed to intragrain-fluxon dynamics [21,22].…”

Section: Discussionmentioning

confidence: 99%

“…Nonlinear electromagnetic response of both conventional and high-T c superconductors has been discussed by different authors [16,17,18,19,20,21,22,23,24,25]. Several mechanisms give rise to emission of signals oscillating at harmonic frequencies of the driving field.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Surface-barrier effects in the microwave second-harmonic response of superconductors in the mixed state

et al. 2005

View full text Add to dashboard Cite

Abstract. We report on transient effects in the microwave second-order response of different type of superconductors in the mixed state. The samples have contemporarily been exposed to a dc magnetic field, varying with a constant rate of 60 Oe/s, and a pulsed microwave magnetic field. The time evolution of the signal radiated at the second-harmonic frequency of the driving field has been measured for about 500 s from the instant in which the dc-field sweep has been stopped, with sampling time of ∼ 0.3 s. We show that the second-harmonic signal exhibits two relaxation regimes; an initial exponential decay, which endures roughly 10 s, and a logarithmic decay in the time scale of minutes. Evidence is given that the decay in the time scale of minutes is ruled by magnetic relaxation over the surface barrier.PACS. 74.25.Ha Magnetic properties -74.25.Nf Response to electromagnetic fields (nuclear magnetic resonance, surface impedance, etc.) -74

show abstract

Section: Discussionmentioning

confidence: 85%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Surface-barrier effects in the microwave second-harmonic response of superconductors in the mixed state

et al. 2005

View full text Add to dashboard Cite

show abstract

“…The first peak appears at a temperature g T slightly below c T , indicating the maximum hysteresis loss which is due to the motion of intra-granular Abrikosov vortices within the superconducting grains [31]. The second loss peak appears at a temperature p T lower than g T and is caused by the motion of inter-granular Josephson coupling [32]. The variation of  versus temperature for (CoFe 2 O 4 ) x GdBa 2 Cu 3 O 7δ (x = 0, 0.01) are shown in Figs.…”

Section: Resultsmentioning

confidence: 96%

The effect of nanosized CoFe2O4 addition on the magnetic properties of GdBa2Cu3O7-δ using AC magnetic susceptibility measurements

et al. 2016

View full text Add to dashboard Cite

Superconductor samples of type (CoFe 2 O 4 ) x GdBa 2 Cu 3 O 7δ (0≤x≤0.1) were synthesized by the conventional solid-state reaction technique, whereas nanosized CoFe 2 O 4 was prepared by co-precipitation method with grain size of about 8.5 nm. The elemental content of the prepared samples was determined using particle induced X-ray emission (PIXE). The temperature dependence of real (  ) and imaginary (  ) components of AC magnetic susceptibility (ACMS) at different magnetic field amplitude (3-15 Oe) was investigated. The analysis of the temperature dependence of ACMS was performed using Bean critical state model. The values of the critical current density c J at T > p T ( p T is the inter-granular loss peak temperature) were calculated as a function of magnetic field and nanosized CoFe 2 O 4 content. It was found that the low nanosized CoFe 2 O 4 addition content (x = 0.01) improves the critical current density c J of Gd-123 superconducting phase. The observed variation of c J with temperature indicated that the weak links are changed from superconductornormal metal-superconductor (SNS) for free sample to superconductor-insulator-superconductor (SIS) type of junctions for samples added with nanosized CoFe 2 O 4 of x > 0.01. We also discussed the experimental results in the framework of the critical state model to estimate the effective volume fraction of the grains g f using Cole-Cole plots.

show abstract

“…It is well known that superconducting materials, especially high-T c superconductors, when exposed to intense electromagnetic fields, show an enhanced nonlinear response [1][2][3][4][5][6][7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%