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Magnetotransport Mechanisms in Strongly Underdoped YBa_2Cu_3O_x Single Crystals

E. Cimpoiasu·G. A. Levin·C. C. Almasan·A. P. Paulikas·B. W. Veal
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Abstract

We report magnetoresistivity measurements on strongly underdoped YBa_2Cu_3O_x (x=6.25, 6.36) single crystals in applied magnetic fields H || c-axis. We identify two different contributions to both in-plane and out-of-plane magnetoresistivities. The first contribution has the same sign as the temperature coefficient of the resistivity \partial ln(ρ_i)/\partial T (i={c,ab}). This contribution reflects the incoherent nature of the out-of-plane transport. The second contribution is positive, quadratic in field, with an onset temperature that correlates to the antiferromagnetic ordering.

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E. Cimpoiasu, G. A. Levin, C. C. Almasan, A. P. Paulikas, B. W. Veal. 2001-09-26. Magnetotransport Mechanisms in Strongly Underdoped YBa_2Cu_3O_x Single Crystals. https://doi.org/10.1103/physrevb.64.104514

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