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arXiv · 0802.2129

Two-dimensional vortex behavior in highly underdoped YBa_2Cu_3O_{6+x} observed by scanning Hall probe microscopy

J. W. Guikema·Hendrik Bluhm·D. A. Bonn·Ruixing Liang·W. N. Hardy·K. A. Moler
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Abstract

We report scanning Hall probe microscopy of highly underdoped superconducting YBa_2Cu_3O_{6+x} with T_c ranging from 5 to 15 K which showed distinct flux bundles with less than one superconducting flux quantum (Phi_0) through the sample surface. The sub-Phi_0 features occurred more frequently for lower T_c, were more mobile than conventional vortices, and occurred more readily when the sample was cooled with an in-plane field component. We show that these features are consistent with kinked stacks of pancake vortices.

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J. W. Guikema, Hendrik Bluhm, D. A. Bonn, Ruixing Liang, W. N. Hardy, K. A. Moler. 2008-02-15. Two-dimensional vortex behavior in highly underdoped YBa_2Cu_3O_{6+x} observed by scanning Hall probe microscopy. https://doi.org/10.1103/physrevb.77.104515

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