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Magnetic-Field Induced Localization in the Normal State of Superconducting La_2-xSr_xCuo_4

A. Malinowski·Marta Z. Cieplak·A. S. van Steenbergen·J. A. A. J. Perenboom·K. Karpinska·M. Berkowski·S. Guha·P. Lindenfeld
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Abstract

Magnetoresistance measurements of highly underdoped superconducting La_{2-x}Sr_xCuO_4 films with $x = 0.051$ and $x = 0.048$, performed in dc magnetic fields up to 20 T and at temperatures down to 40 mK, reveal a magnetic-field induced transition from weak to strong localization in the normal state. The normal-state conductances per CuO_2--plane, measured at different fields in a single specimen, are found to collapse to one curve with the use of a single scaling parameter that is inversely proportional to the localization length. The scaling parameter extrapolates to zero near zero field and possibly at a finite field, suggesting that in the zero-field limit the electronic states may be extended.

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A. Malinowski, Marta Z. Cieplak, A. S. van Steenbergen, J. A. A. J. Perenboom, K. Karpinska, M. Berkowski, S. Guha, P. Lindenfeld. 1997-05-14. Magnetic-Field Induced Localization in the Normal State of Superconducting La_2-xSr_xCuo_4. https://doi.org/10.1103/physrevlett.79.495

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