Three-Dimensional Fermi Surface of Overdoped La-Based Cuprates

M. Horio; K. Hauser; Y. Sassa; Z. Mingazheva; D. Sutter; K. Kramer; A. Cook; E. Nocerino; O. K. Forslund; O. Tjernberg; M. Kobayashi; A. Chikina; N. B. M. Schröter; J. A. Krieger; T. Schmitt; V. N. Strocov; S. Pyon; T. Takayama; H. Takagi; O. J. Lipscombe; S. M. Hayden; M. Ishikado; H. Eisaki; T. Neupert; M. Månsson; C. E. Matt; J. Chang

doi:10.1103/physrevlett.121.077004

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arXiv · 1804.08019

Three-Dimensional Fermi Surface of Overdoped La-Based Cuprates

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Abstract

We present a soft x-ray angle-resolved photoemission spectroscopy study of the overdoped high-temperature superconductors La$_{2-x}$Sr$_x$CuO$_4$ and La$_{1.8-x}$Eu$_{0.2}$Sr$_x$CuO$_4$. In-plane and out-of-plane components of the Fermi surface are mapped by varying the photoemission angle and the incident photon energy. No $k_z$ dispersion is observed along the nodal direction, whereas a significant antinodal $k_z$ dispersion is identified. Based on a tight-binding parametrization, we discuss the implications for the density of states near the van-Hove singularity. Our results suggest that the large electronic specific heat found in overdoped La$_{2-x}$Sr$_x$CuO$_4$ can not be assigned to the van-Hove singularity alone. We therefore propose quantum criticality induced by a collapsing pseudogap phase as a plausible explanation for observed enhancement of electronic specific heat.

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M. Horio, K. Hauser, Y. Sassa, Z. Mingazheva, D. Sutter, K. Kramer, A. Cook, E. Nocerino, O. K. Forslund, O. Tjernberg, M. Kobayashi, A. Chikina, N. B. M. Schröter, J. A. Krieger, T. Schmitt, V. N. Strocov, S. Pyon, T. Takayama, H. Takagi, O. J. Lipscombe, S. M. Hayden, M. Ishikado, H. Eisaki, T. Neupert, M. Månsson, C. E. Matt, J. Chang. 2018-04-21. Three-Dimensional Fermi Surface of Overdoped La-Based Cuprates. https://doi.org/10.1103/physrevlett.121.077004

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