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Pseudogap Induced by Superconducting Fluctuation in the d-p Model

Akito Kobayashi·Atsushi Tsuruta·Tamifusa Matsuura·Yoshihiro Kuroda
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Abstract

Using the d-p model, we demonstrate that the pseudogap, which is induced by the superconducting fluctuation, plays key roles in the determination of the phase diagram observed in high-Tc superconducting materials. We take the pairing interaction mediated by the spin fluctuation and calculate the superconducting transition temperature Tc, the NMR relaxation rate 1/T1 and the single-particle spectrum by treating both the superconducting fluctuation and spin fluctuation in a consistent fashion. As temperature decreases, 1/T1T increases at high temperatures, and it reaches a maximum followed by a sharp drop in the underdoped region, due to the evolution of the pseudogap in the single-particle spectrum. The evolution is also consistent with those of ARPES experiments.

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Akito Kobayashi, Atsushi Tsuruta, Tamifusa Matsuura, Yoshihiro Kuroda. 1999-07-01. Pseudogap Induced by Superconducting Fluctuation in the d-p Model. https://doi.org/10.1143/jpsj.68.2506

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