Schematic representation of the postulated distribution in the boundary planes along the c-axis of the YBCO films. The dotted lines represent the Josephson weak links rows and the solid lines are the borders of the domains with different critical temperatures, . In the figure we have supposed that the boundary planes include n domains with different , consisting of weak links rows.
Surface critical current density of film LEY9275. The full symbols are calculated with Eq. (3) from the magnetic moment measurements and the solid line with Eqs. (5)–(7) and the data in Table II. The dotted line shows the contribution of the domain with the highest and the inset shows the same curves on a logarithmic scale.
Maximum surface critical current density at low temperature of the investigated films, , as a function of the total number of Josephson weak links rows, , included in their boundary planes. The symbols correspond to different deposition surfaces. The straight line is a guide for the eye.
Deposited thickness, , of the investigated films as a function of , the total number of Josephson weak links rows included in their boundary planes. The symbols correspond to different deposition surfaces and the straight line connects the samples with the largest .
Maximum surface critical current density at low temperature of the films with the largest , , as a function of their deposited thickness, .
Critical temperature as a function of the distance z to the surface in film LEY9275.
Magnetic moment of film LEY9275 measured in the field cooled conditions as a function of the temperature with a 2 mT field (a) and a 3 mT field (b). The filled and open squares are, respectively, the experimental measurements and the values calculated with the data in Table III using Eq. (14).
Critical temperature as a function of the distance z to the surface in film LEY9047 and of the zones investigated by NRERS according to the data by Cava et al. (Ref. 26), Jorgensen et al. (Ref. 27), and Moran et al. (Ref. 28).
Critical temperature as a function of the distance z to the surface in film LEY8992. The of the zones investigated by NRERS according to the data by Cava et al. (Ref. 26), Jorgensen et al. (Ref. 27) and Moran et al.(Ref. 28) are reported (i) without correction in (a) and (ii) supposing that there is a 25 nm thick nonsuperconducting layer at the film surface in (b).
Dependence of the relative thickness of the high plateau, , with the thickness, , for the films deposited on STO whose superconducting and deposited thicknesses are equal.
Deposition surface, deposition temperature , oxygen pressure during and after the deposition step, and , respectively, of some of the investigated films. The heating system (Joule effect or halogen lamps) is also reported. For some films an oxygenation step was included in the fabrication process. In this case, and are, respectively, the duration and the temperature of this step, v is the cooling rate after deposition, the deposited thickness (±10 nm) and the transition temperature to the nonresistive state.
distribution in film LEY9275: and are the superconducting and the deposited thickness of the film; and are the number of Josephson weak links rows and the thickness of the domains with critical temperature , respectively.
Deposited , and superconducting thicknesses of the samples in Table I, calculated either as or as .
Oxygen content in zones Z1 and Z2 of films LEY9047 and LEY8992, as determined by NRERS; is the deposited thickness of the films and their superconducting thickness calculated as indicated in Table II.
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