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arXiv · 1001.4916

STM/STS study on large pseudogap and nodal superconducting gap in Bi2201(La) and Bi2212

T. Kurosawa·T. Yoneyama·Y. Takano·M. Hagiwara·R. Inoue·N. Hagiwara·K. Kurusu·K. Takeyama·N. Momono·M. Oda·M. Ido
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Abstract

In the present work, scanning tunneling microscopy/spectroscopy (STM/STS) measurements were carried out on underdoped $\rm Bi_2Sr_{2-{\it x}}La_{\it x}CuO_{6+δ}$ and $\rm Bi_2Sr_2CaCu_2O_{8+δ}$ to clarify the origin of the pseudogap, in particular, the inhomogeneous large pseudogap. The nodal part of a d-wave pairing gap, which is under no influence of the inhomogeneous large pseudogap, was also examined by relating the homogeneous bottom part of the STS gap to a nodal d-wave gap in momentum space. We report that the inhomogeneous large pseudogap in the antinodal region links to a two-dimensional electronic charge order, and that the gap size of the nodal d-wave part $\rm Δ_{sc}$ scales with the superconducting critical temperature $\rm {\it T}_c$ in the pseudogap regime.

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T. Kurosawa, T. Yoneyama, Y. Takano, M. Hagiwara, R. Inoue, N. Hagiwara, K. Kurusu, K. Takeyama, N. Momono, M. Oda, M. Ido. 2010-01-27. STM/STS study on large pseudogap and nodal superconducting gap in Bi2201(La) and Bi2212. https://arxiv.org/abs/1001.4916

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