Two-dimensional weak localization effects in high temperature superconductor Nd{2-x}Ce{x}CuO{4-d}

G. I. Harus; A. N. Ignatenkov; A. I. Ponomarev; L. D. Sabirzyanova; N. G. Shelushinina; A. A. Ivanov

doi:10.1134/1.558934

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Two-dimensional weak localization effects in high temperature superconductor Nd{2-x}Ce{x}CuO{4-d}

G. I. Harus·A. N. Ignatenkov·A. I. Ponomarev·L. D. Sabirzyanova·N. G. Shelushinina·A. A. Ivanov

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Abstract

A systematic study of the resistivity and Hall effect in single crystal Nd{2-x}Ce{x}CuO{4-d} films (0.12 < x < 0.20) is presented, with special emphasis on the low-temperature dependence of the normal state conductance. Two-dimensional weak localization effects are found both in a normally conducting underdoped sample (x = 0.12) and in situ superconducting optimally doped (x = 0.15) or overdoped (x = 0.18) samples in a high magnetic field B > B{c2}. The phase coherence time and the effective thickness of a CuO{2} conducting layer {d} (~ 1.5 A) have been estimated by fitting 2D weak localization theory expressions to the magnetoresistivity data for magnetic fields perpendicular to the {ab} plane and in plane. Estimates of the parameter {d} ensure the condition of strong carrier confinement and justify a model consisting of almost decoupled 2D metallic sheets for the Nd{2-x}Ce{x}CuO{4-d} single crystal.

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G. I. Harus, A. N. Ignatenkov, A. I. Ponomarev, L. D. Sabirzyanova, N. G. Shelushinina, A. A. Ivanov. 1999-12-01. Two-dimensional weak localization effects in high temperature superconductor Nd{2-x}Ce{x}CuO{4-d}. https://doi.org/10.1134/1.558934

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