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Magnetoconductivity due to Quantum Interference in Strongly Underdoped YBa_2Cu_3O_x

E. Cimpoiasu·G. A. Levin·C. C. Almasan·Hong Zheng·B. W. Veal
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Abstract

We report magnetoconductivity measurements on YBa_2Cu_3O_x (x=6.25 and 6.36) single crystals. Our main result is that both the in-plane Delta_sigma_ab and out-of-plane Delta_sigma_c magnetoconductivities exhibit the field dependence characteristic of "two-dimensional" quantum interference in applied magnetic fields H parallel to the c-axis. Namely, Delta_sigma_c,ab are proportional to ln(H/H_0), with Delta_sigma_c/sigma_c substantially greater than Delta_sigma_ab/sigma_ab. We interpret this result as evidence of interlayer incoherence in these crystals, so that the phase-coherent trajectories are mostly confined to one bilayer.

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E. Cimpoiasu, G. A. Levin, C. C. Almasan, Hong Zheng, B. W. Veal. 2001-04-03. Magnetoconductivity due to Quantum Interference in Strongly Underdoped YBa_2Cu_3O_x. https://doi.org/10.1103/physrevb.63.104515

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