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Metal-to-Insulator Crossover in the Low-Temperature Normal State of Bi_{2}Sr_{2-x}La_{x}CuO_{6+δ}

S. Ono·Yoichi Ando·T. Murayama·F. F. Balakirev·J. B. Betts·G. S. Boebinger
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Abstract

We measure the normal-state in-plane resistivity of La-doped Bi-2201 single crystals at low temperatures by suppressing superconductivity with 60-T pulsed magnetic fields. With decreasing hole doping, we observe a crossover from a metallic to insulating behavior in the low-temperature normal state. This crossover is estimated to occur near 1/8 doping, well inside the underdoped regime, and not at optimum doping as reported for other cuprates. The insulating regime is marked by a logarithmic temperature dependence of the resistivity over two decades of temperature, suggesting that a peculiar charge localization is common to the cuprates.

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S. Ono, Yoichi Ando, T. Murayama, F. F. Balakirev, J. B. Betts, G. S. Boebinger. 2000-05-26. Metal-to-Insulator Crossover in the Low-Temperature Normal State of Bi_{2}Sr_{2-x}La_{x}CuO_{6+δ}. https://doi.org/10.1103/physrevlett.85.638

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