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Columnar defects acting as passive internal field detectors

A. V. Silhanek·L. Civale·M. A. Avila
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Abstract

We have studied the angular dependence of the irreversible magnetization of several YBa$_2$Cu$_3$O$_7$ and 2H-NbSe$_2$ single crystals with columnar defects tilted off the c-axis. At high magnetic fields, the irreversible magnetization $M_i(Θ_H)$ exhibits a well known maximum when the applied field is parallel to the tracks. As the field is decreased below $H \sim 0.02 H_{c2}$, the peak shifts away from the tracks' direction toward either the c-axis or the ab-planes. We demonstrate that this shift results from the misalignment between the external and internal field directions due to the competition between anisotropy and geometry effects.

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A. V. Silhanek, L. Civale, M. A. Avila. 2001-10-30. Columnar defects acting as passive internal field detectors. https://doi.org/10.1103/physrevb.65.174525

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