ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The fluence dependence of the composition of pulsed-laser deposited YBa2Cu3O7−δ films is investigated and interpreted in terms of laser-induced target modification. Both target degradation (at fluence J〈1.0 J/cm2) and diffusion-assisted preferential ablation (1.0〈J〈1.3 J/cm2) are found to be responsible for nonstoichiometric transfer. A one-dimensional, moving-boundary diffusion model is developed to describe diffusion-assisted preferential ablation. This model predicts stoichiometric transfer at large ablation rates. Indeed, for J(very-much-greater-than)1.3 J/cm2 stoichiometric deposition is found, resulting in precipitate-free films. However, slightly off-stoichiometric films, deposited in the diffusion-assisted preferential ablation regime, exhibit the best superconducting properties (Tc=91.0 K, ΔTc=0.4 K) and can be produced with a remarkably high reproducibility. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.371619
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