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Negative Hopping Magnetoresistance and Dimensional Crossover in Lightly Doped Cuprate Superconductors

Valeri N. Kotov·Oleg P. Sushkov·M. B. Silva Neto·L. Benfatto·A. H. Castro Neto
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Abstract

We show that, due to the weak ferromagnetism of La$_{2-x}$Sr$_x$CuO$_4$, an external magnetic field leads to a dimensional crossover 2D $\to$ 3D for the in-plane transport. The crossover results in an increase of the hole's localization length and hence in a dramatic negative magnetoresistance in the variable range hopping regime. This mechanism quantitatively explains puzzling experimental data on the negative magnetoresistance in the Néel phase of La$_{2-x}$Sr$_x$CuO$_4$.

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Valeri N. Kotov, Oleg P. Sushkov, M. B. Silva Neto, L. Benfatto, A. H. Castro Neto. 2007-12-14. Negative Hopping Magnetoresistance and Dimensional Crossover in Lightly Doped Cuprate Superconductors. https://doi.org/10.1103/physrevb.76.224512

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