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Two mechanisms of pseudogap formation in Bi-2201: Evidence from the c-axis magnetoresistance

A. N. Lavrov·Yoichi Ando·S. Ono
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Abstract

Measurements of the c-axis resistivity and magnetoresistance have been used to investigate the pseudogap (PG) behavior in Bi_{2+z}Sr_{2-x-z}La_xCuO_y (Bi-2201) crystals at various hole densities. While the PG opening temperature T* increases with decreasing hole doping, the magnetic-field sensitivity of the PG is found to have a very different trend: it appears at lower temperatures in more underdoped samples and vanishes in non-superconducting samples. These data suggest that besides the field-insensitive pseudogap emerging at T*, a distinct one is formed above T_c as a precursor to superconductivity.

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A. N. Lavrov, Yoichi Ando, S. Ono. 2001-11-01. Two mechanisms of pseudogap formation in Bi-2201: Evidence from the c-axis magnetoresistance. https://doi.org/10.1209/epl%2Fi2002-00571-0

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