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Microwave properties of YBa$_2$Cu$_3$O$_{7-δ}$ films with BaZrO$_3$ nanoinclusions

N. Pompeo·E. Silva·R. Marcon·V. Galluzzi·G. Celentano·A. Augieri·T. Petrisor
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Abstract

We present measurements of the microwave complex surface impedance at 47.7 GHz in YBa$_2$Cu$_3$O$_{7-δ}$ (YBCO) films deposited by pulsed laser deposition with the explicit goal to introduce BaZrO$_3$ (BZO) nanoinclusions. Composite targets obtained by addition of BZO powder in molar percents ranging from 2.5 to 7 mol.% have been prepared and characterized. Measurements of the microwave surface impedance indicate a broadened transition in zero field, however compensated by a very large pinning frequency, indicating that while intergrain properties are still to be optimized the effect of nanometric inclusions substantially enhances the intragrain vortex pinning.

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N. Pompeo, E. Silva, R. Marcon, V. Galluzzi, G. Celentano, A. Augieri, T. Petrisor. 2006-10-23. Microwave properties of YBa$_2$Cu$_3$O$_{7-δ}$ films with BaZrO$_3$ nanoinclusions. https://doi.org/10.1016/j.physc.2007.03.104

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