High-quality single phase Nd1+xBa2−xCu3O7−d thin films have been fabricated on SrTiO3 substrates by the laser ablation method. The resistivity of the deposited films are usually lower than that of the YBCO film. The Tc(onset) and Tc(R=0) in the optimized thin films are as high as 91 and 88 K, respectively. The crystallinity of our films are higher than the best YBCO films ever reported. The rocking curve FWHM of the (005) peaks in our thin films is typically 0.05°, which is superior to the best reported YBCO films.

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It is demonstrated that (NBCO) thin films, deposited by laser ablation, show extraordinary properties which are unprecedented in the 123 system. These include ease of oxidation, very high crystallinity, surface stability, and a relatively high . The properties of NBCO thin films are compared with those of the best reported films, and the origins of their differences are discussed. The implications of NBCO's superior thin-film quality in the context of device applications are also addressed throughout the paper.

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The time-of-flight (TOF) measurements for ions in the expanding plume during laser ablation of Y1Ba2Cu3Ox are performed. The TOF spectra consist of peaks of only the monatomic ions. The drift velocities for these ions are revealed to be (2–4)×106 cm/s at the laser fluence of 2.0 J/cm2 and an oxygen pressure of 10−3 Torr. These velocities are affected by the ablation conditions, and are found to increase with increasing laser fluence and decrease with increase of oxygen pressure. The velocity distributions for the ions at high oxygen pressure are described by the supersonic expansion model with a distribution width narrowing with decreasing oxygen pressure.