Evidence of strong correlations at the van Hove singularity in the scanning tunneling spectra of superconducting Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} single crystals

Jouko Nieminen; Ilpo Suominen; Tanmoy Das; R. S. Markiewicz; A. Bansil

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arXiv · 1205.5540

Evidence of strong correlations at the van Hove singularity in the scanning tunneling spectra of superconducting Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} single crystals

Jouko Nieminen·Ilpo Suominen·Tanmoy Das·R. S. Markiewicz·A. Bansil

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Abstract

We present realistic multiband calculations of scanning tunneling spectra in Bi_{2}Sr_{2}CaCu_{2} O_{8+\delta} over a wide doping range. Our modeling incorporates effects of a competing pseudogap and pairing gap as well as effects of strong electronic correlations, which are included by introducing self-energy corrections in the one-particle propagators. The calculations provide a good description of the two-gap features seen in experiments at low energies and the evolution of the Van Hove singularity (VHS) with doping, and suggest a possible quantum critical point near the point where the VHS crosses the Fermi level.

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Jouko Nieminen, Ilpo Suominen, Tanmoy Das, R. S. Markiewicz, A. Bansil. 2012-05-24. Evidence of strong correlations at the van Hove singularity in the scanning tunneling spectra of superconducting Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} single crystals. https://arxiv.org/abs/1205.5540

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