YBCO films were prepared by pulsed laser deposition from nanocrystalline targets doped with different concentrations of BaZrO 3 ranging from c = 0.9 to 9.0 wt%. The critical temperature of the films decreases almost linearly with increasing BaZrO 3 content whereas the critical current density shows a maximum near 3.9 wt%. In comparison with undoped YBCO films the accommodation field B * is considerably enhanced and the critical current density is improved in high fields in the films doped with BaZrO 3 , e.g. for c = 3.9 wt% by factor of 4.5 in a field of 5 T at 5 K. In the doped films the BaZrO 3 particles grow epiaxially with YBCO. Transmission electron microscopy results show that the density of the BaZrO 3 particles increases with increasing doping but the particle size remains practically the same (5-10 nm).

Achieving low cost, safe, reproducible and high performance superconducting thin films of YBa2Cu3O7-δ is essential to bring this material to the energy market. Here, we report on the chemical solution deposition of YBa2Cu3O7-δ nanocomposites from environmentally benign precursors with a low-fluorine content. Preformed ZrO2 nanocrystals (3.5 nm) were stabilized in a methanolic precursor solution via two strategies: charge stabilization and steric stabilization. Counter-intuitively, charge stabilization did not result in high quality superconducting layers, while the steric stabilization resulted in highly reproducible nanocomposite thin films with a self-field Jc of 4-5 MA cm -² (77 K) and a much smaller decay of Jc with magnetic field compared to YBa2Cu3O7-δ without nanocrystals. In addition, these nanocomposite films show a strong pinning force enhancement and a reduced Jc anisotropy compared to undoped YBa2Cu3O7-δ films. Given the relationship between the nanocrystal surface chemistry and final nanocomposite performance, we expect these results to be also relevant for other nanocomposite research.-2 -

The activation energy of nature-inspired hackmanites was tuned, adapting this material for UV detection.

The present paper reports detailed structural and magnetic characterization of the low-bandwidth manganite Pr(1-x)Ca(x)MnO(3) (with x = 0.0-0.5) (PCMO) polycrystalline samples. With increasing Ca content, reduction of the unit cell volume and improvement in perovskite structure symmetry was observed at room temperature. Magnetic characterization shows the signature of coexisting AFM-FM ordering and spin-glass phase at the low doping range (x = 0.0-0.2) while increased hole doping (x = 0.3-0.5) leads to charge ordering, training effect and an irreversible metamagnetic phenomenon. The large irreversible metamagnetism in the CO phase of PCMO and the corresponding spin memory effect is a direct consequence of hysteretic first-order phase transition arising from the weakening of the CO state under the external magnetic field and trapping of the spins due to a strong pinning potential in the material.