Directional vortex pinning at microwave frequency in YBa$_{2}$Cu$_3$O$_{7-x}$ thin films with BaZrO$_3$ nanorods

N. Pompeo; K. Torokhtii; A. Augieri; G. Celentano; V. Galluzzi; E. Silva

paper

Directional vortex pinning at microwave frequency in YBa $_{2}$ Cu $_{3}$ O $_{7 - x}$ thin films with BaZrO $_{3}$ nanorods

arXiv:1210.7232

Abstract

We investigate the effect of the anisotropy and of the directional pinning in YBa $_{2}$ Cu $_{3}$ O $_{7 - x}$ films grown by pulsed laser ablation from targets containing BaZrO $_{3}$ at 5% mol. BaZrO $_{3}$ inclusions self-assemble to give nanorods oriented along the c-axis, thus giving a preferential direction for vortex pinning. The directionality of vortex response is studied at high ac frequency with the complex microwave response at 48 GHz, as a function of the applied field and of the angle $θ$ between the field and the c-axis. The complex microwave response does not exhibit any angular scaling, suggesting that the structural anisotropy of YBa $_{2}$ Cu $_{3}$ O $_{7 - x}$ is supplemented by at least another preferred orientation. The pinning parameter $r$ shows evidence of directional pinning, effective in a wide range of angles around the c-axis (thus ascribed to BZO nanocolumns).

9 pages, 4 figures, submitted to J. Supercond. Nov. Magn

Directional vortex pinning at microwave frequency in YBa2​Cu3​O7−x​ thin films with BaZrO3​ nanorods

Abstract

Directional vortex pinning at microwave frequency in YBa $_{2}$ Cu $_{3}$ O $_{7 - x}$ thin films with BaZrO $_{3}$ nanorods