Ultrahigh-Speed Pulsed Laser Deposition of YBCO Layer in Processing of Long HTS Coated Conductors

Pulsed laser deposition (PLD) is classically considered as a very reliable process that provides correct stoichiometry of the deposited layer when the deposition speed is below 0.1 nm per deposition pulse. Initially, we found significant critical currents of 200-400 A/cm-width by very high deposition rates. Later, in this work, a study of reproducibility and feasibility of high- and ultrahigh-speed PLD is performed. With high speed, we denote a range from 0.1 to 0.3 nm/pulse, whereas ultrahigh speed corresponds to higher numbers, i.e., above 0.3 nm/pulse. At ultrahigh laser energy density, an optimum deposition rate is found that maximizes the critical current, i.e., I
_c
. The I
_c
at this maximum may reach 500-700 A/cm-width by relatively low (<; 1.5 MA/cm
²
) J
_c
. The optimal deposition rate and energy density may be employed in cost-feasible technological solutions because deposition time may be shortened by a factor of ~5. A suggested double-layer model with different critical currents in layers provides good fitting of the experimental dependence.