Intermediate coupling model of cuprates: adding fluctuations to a weak coupling model of pseudogap and superconductuctivity competition

R. S. Markiewicz; Tanmoy Das; Susmita Basak; A. Bansil

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arXiv · 1002.0106

Intermediate coupling model of cuprates: adding fluctuations to a weak coupling model of pseudogap and superconductuctivity competition

R. S. Markiewicz·Tanmoy Das·Susmita Basak·A. Bansil

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Abstract

We demonstrate that many features ascribed to strong correlation effects in various spectroscopies of the cuprates are captured by a calculation of the self-energy incorporating effects of spin and charge fluctuations. The self energy is calculated over the full doping range from half filling to the overdoped system. In the normal state, the spectral function reveals four subbands: two widely split incoherent bands representing the remnant of the two Hubbard bands, and two additional coherent, spin- and charge-dressed in-gap bands split by a spin-density wave, which collapses in the overdoped regime. The resulting coherent subbands closely resemble our earlier mean-field results. Here we present an overview of the combined results of our mean-field calculations and the newer extensions into the intermediate coupling regime.

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R. S. Markiewicz, Tanmoy Das, Susmita Basak, A. Bansil. 2010-01-31. Intermediate coupling model of cuprates: adding fluctuations to a weak coupling model of pseudogap and superconductuctivity competition. https://arxiv.org/abs/1002.0106

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